@prefix vivo: . @prefix edm: . @prefix ns0: . @prefix dcterms: . @prefix skos: . vivo:departmentOrSchool "Applied Science, Faculty of"@en, "Materials Engineering, Department of"@en ; edm:dataProvider "DSpace"@en ; ns0:degreeCampus "UBCV"@en ; dcterms:creator "Norrish, Norman Ian"@en ; dcterms:issued "2010-01-21T22:40:31Z"@en, "1974"@en ; vivo:relatedDegree "Master of Applied Science - MASc"@en ; ns0:degreeGrantor "University of British Columbia"@en ; dcterms:description """Laboratory and in situ testing programmes to determine the deformation behaviour of three rock types have provided an opportunity for a comparison of three testing techniques. To aid future standardization, procedures and equipment for the laboratory testing, Goodman Jack testing and plate loading tests are presented in detail. Laboratory tests and plate loading tests show that the gneiss and schist rock types are well differentiated on the basis of deformation modulus. The ratio of average modulus for gneiss to schist is 2.0 from the laboratory testing and 5.6 for the plate loading tests. The Goodman Jack modulus values are similar for all rock types, the ratio of gneiss to schist being 1.3. Similarly the laboratory and plate loading tests show a wide range of values while the jack tests exhibit a very narrow range. The modulus results for the schist conform to the anticipated scale effect while the gneiss tests do not. It is concluded that the partial correlation between the three testing techniques reflects the need to quantify important factors such as rock quality and in situ stresses and to incorporate these factors into valid interpretive formulae. Anisotropy investigations for the laboratory and plate loading tests are consistent. The schist is approximately twice as rigid loaded parallel to the foliation than when loaded perpendicular to it. Anisotropy investigations with the Goodman Jack are qualitative only without very detailed geologic information at the test locations. Permanent deformations of the rock are consistent for the three testing methods and reflect the volume of rock influenced as well as the rock quality at the test location."""@en ; edm:aggregatedCHO "https://circle.library.ubc.ca/rest/handle/2429/18882?expand=metadata"@en ; skos:note "A COMPARISON OF THREE TECHNIQUES FOR THE DETERMINATION OF DEFORMATION PROPERTIES OF ROCK by NORMAN IAN NORRISH B . A . S c , U n i v e r s i t y o f B r i t i s h C o l u m b i a , 1971 A THESIS SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF APPLIED SCIENCE i n t h e Depa r tment o f M i n e r a l E n g i n e e r i n g We a c c e p t t h i s t h e s i s as c o n f o r m i n g t o t h e r e q u i r e d s t a n d a r d THE UNIVERSITY OF BRITISH COLUMBIA A p r i l , 1974 I n p r e s e n t i n g t h i s t h e s i s - i n p a r t i a l f u l f i l m e n t o f t h e r e q u i r e m e n t s f o r a n a d v a n c e d d e g r e e a t t h e U n i v e r s i t y o f B r i t i s h C o l u m b i a , I a g r e e t h a t t h e L i b r a r y s h a l l m a k e i t f r e e l y a v a i l a b l e f o r r e f e r e n c e a n d s t u d y . I f u r t h e r a g r e e t h a t p e r m i s s i o n f o r e x t e n s i v e c o p y i n g o f t h i s t h e s i s f o r s c h o l a r l y p u r p o s e s may be g r a n t e d by t h e H e a d o f my D e p a r t m e n t o r by h i s r e p r e s e n t a t i v e s . I t i s u n d e r s t o o d t h a t c o p y i n g o r p u b l i c a t i o n o f t h i s t h e s i s f o r f i n a n c i a l g a i n s h a l l n o t be a l l o w e d w i t h o u t my w r i t t e n p e r m i s s i o n . D e p a r t m e n t o f ^1jsv^dL £^joys*ju>Ajs^ T h e U n i v e r s i t y o f B r i t i s h C o l u m b i a V a n c o u v e r 8 , C a n a d a D a t e ApuX ^ , )°i~>4 ABSTRACT L a b o r a t o r y and in situ t e s t i n g programmes t o d e t e r m i n e t h e d e f o r m a t i o n b e h a v i o u r o f t h r e e r o c k t y p e s have p r o v i d e d an o p p o r t u n i t y f o r a c o m p a r i s o n o f t h r e e t e s t i n g t e c h n i q u e s . To a i d f u t u r e s t a n d a r d i z a t i o n , p r o c e d u r e s and e q u i p m e n t f o r t h e l a b o r a t o r y t e s t i n g , Goodman J a c k t e s t i n g and p l a t e l o a d i n g t e s t s a r e p r e s e n t e d i n d e t a i l . L a b o r a t o r y t e s t s and p l a t e l o a d i n g t e s t s show t h a t t h e g n e i s s and s c h i s t r o c k t y p e s a r e w e l l d i f f e r e n t i a t e d on t h e b a s i s o f d e f o r m a t i o n m o d u l u s . The r a t i o o f a v e r a g e modulus f o r g n e i s s t o s c h i s t i s 2 . 0 f r o m t h e l a b o r a t o r y t e s t i n g and 5 . 6 f o r t h e p l a t e l o a d i n g t e s t s . The Goodman J a c k modulus v a l u e s a r e s i m i l a r f o r a l l r o c k t y p e s , t h e r a t i o o f g n e i s s t o s c h i s t b e i n g 1 . 3 . S i m i l a r l y t h e l a b o r a t o r y and p l a t e l o a d i n g t e s t s show a w i d e r a n g e o f v a l u e s w h i l e t h e j a c k t e s t s e x h i b i t a v e r y n a r r o w r a n g e . The modu lus r e s u l t s f o r t h e s c h i s t c o n f o r m t o the a n t i c i p a t e d s c a l e e f f e c t w h i l e t h e g n e i s s t e s t s do n o t . I t i s c o n c l u d e d t h a t t h e p a r t i a l c o r r e l a t i o n between t h e t h r e e t e s t i n g t e c h n i q u e s r e f l e c t s t h e need t o q u a n t i f y i m p o r t a n t f a c t o r s s u c h as r o c k q u a l i t y and in situ s t r e s s e s and t o i n c o r p o r a t e t h e s e f a c t o r s i n t o v a l i d i n t e r p r e t i v e f o r m u l a e . A n i s o t r o p y i n v e s t i g a t i o n s f o r t h e l a b o r a t o r y and p l a t e l o a d i n g t e s t s a r e c o n s i s t e n t . The s c h i s t i s a p p r o x i m a t e l y t w i c e as r i g i d l o a d e d p a r a l l e l t o t h e f o l i a t i o n t h a n when l o a d e d p e r p e n d i c u l a r t o i t . A n i s o t r o p y i n v e s t i g a t i o n s w i t h t h e Goodman J a c k a r e q u a l i t a t i v e o n l y i v w i t h o u t v e r y d e t a i l e d g e o l o g i c i n f o r m a t i o n a t t h e t e s t l o c a t i o n s . Permanent d e f o r m a t i o n s o f t h e r o c k a r e c o n s i s t e n t f o r t h e t h r e e t e s t i n g methods and r e f l e c t t h e volume o f r o c k i n f l u e n c e d as w e l l as t h e r o c k q u a l i t y a t t h e t e s t l o c a t i o n . V ACKNOWLEDGEMENTS F o r p r o v i d i n g e q u i p m e n t and f a c i l i t i e s , t h e a u t h o r w o u l d l i k e t o t h a n k t h e M i n e r a l E n g i n e e r i n g Depar tment o f t h e U n i v e r s i t y o f B r i t i s h C o l u m b i a . Thanks a r e e s p e c i a l l y due Mr . J . B . E v a n s , Depar tment H e a d , and Dr . I. W e i r - J o n e s , programme s u p e r v i s o r . The a u t h o r a l s o t h a n k s t h e p r o f e s s i o n a l e n g i n e e r i n g g roup t h a t c o n t r i b u t e d d a t a and r e v i e w e d t h e d r a f t t h e s i s . v i TABLE OF CONTENTS C h a p t e r Page I . INTRODUCTION 1 I I . BACKGROUND TO TESTING PROGRAMMES 3 I I I . DESCRIPTION OF TEST SITE 4 A. I n t r o d u c t i o n 4 B. G e o l o g y o f t h e T e s t S i t e 4 I V . REVIEW OF TESTING PROGRAMMES 6 A . L a b o r a t o r y T e s t i n g Programme 6 1 . Sample P r e p a r a t i o n 6 2 . Load Measurement 8 3 . S t r a i n Measurement 11 4 . T e s t P r o c e d u r e 17 5 . Summary . 18 B. Goodman J a c k T e s t i n g 18 1 . D e s c r i p t i o n o f Equ ipment 18 2 . P r o c e d u r e 23 C. P l a t e L o a d i n g T e s t s 27 1 . D e s c r i p t i o n o f Equ ipment 27 2 . P r o c e d u r e 29 V. INTERPRETATION OF TEST DATA 31 A . L a b o r a t o r y T e s t i n g Programme 31 B. Goodman J a c k T e s t i n g 31 C. P l a t e Load T e s t s 35 D. D e f i n i t i o n o f Modu lus Types 37 v i i C h a p t e r Page V I . RESULTS OF TESTING PROGRAMMES 42 A . L a b o r a t o r y T e s t i n g Programme 42 1 . Q u a r t z i t e G n e i s s 44 2 . Q u a r t z F e l d s p a r S c h i s t 53 3. P e g m a t i t e 67 4 . Summary and C o m p a r i s o n o f L a b o r a t o r y R e s u l t s 71 B. Goodman J a c k T e s t i n g 74 1 . Q u a r t z i t e G n e i s s 77 2 . Q u a r t z F e l d s p a r S c h i s t 84 3. P e g m a t i t e 96 4 . Summary and C o m p a r i s o n o f Goodman ' J a c k R e s u l t s 96 C. P l a t e L o a d i n g T e s t s 101 V I I . COMPARISON OF TESTING TECHNIQUES 108 A. M a g n i t u d e o f M o d u l i 108 1 . F a c t o r s R e l e v e n t t o C o m p a r i s o n 108 2 . O b s e r v a t i o n s on t h e T h r e e Groups o f Modulus R e s u l t s 110 3 . D i s c u s s i o n o f t h e Modu lus R e s u l t s I l l B. A n i s o t r o p y 114 C. E l a s t i c R e c o v e r y 114 D. Ease o f P e r f o r m a n c e 115 E. E v a l u a t i o n o f T e s t i n g T e c h n i q u e s 116 1 . L a b o r a t o r y T e s t i n g 117 2 . Goodman J a c k T e s t i n g 118 v i i i C h a p t e r Page 3 . P l a t e L o a d i n g T e s t s 1 2 1 V I I I . CONCLUSION 1 2 3 BIBLIOGRAPHY 1 2 5 APPENDICES 1 2 8 i x L IST OF TABLES T a b l e Page 1. Summary o f L a b o r a t o r y T e s t i n g Programme 19 2 . Summary o f L a b o r a t o r y R e s u l t s 78 3 . Summary o f Goodman J a c k R e s u l t s 98 4 . R e s u l t s o f P l a t e L o a d i n g T e s t s 102 X L I S T OF FIGURES F i g u r e Page 1 . P r e p a r a t i o n o f C o r e Samples U s i n g \"B lohm S i m p l e x \" S u r f a c e G r i n d e r 7 2 . H y d r a u l i c P r e s s and I n s t r u m e n t a t i o n f o r L a b o r a t o r y T e s t i n g 9 3 . C a l i b r a t i o n o f Load C e l l and Readout U n i t 10 4 . Dep loyment o f S t r a i n Gauges f o r t h e T h r e e Rock Types 13 5 . P l a c e m e n t o f S t r a i n Gauges R e l a t i v e t o S t r i k e and D ip D i r e c t i o n s f o r Q u a r t z F e l d s p a r S c h i s t Samples . . . . 14 6. D i s a s s e m b l e d Goodman J a c k 20 7 . A s s e m b l e d Goodman J a c k , T r a n s d u c e r Readout U n i t and H y d r a u l i c Pump 22 8 . O r i e n t a t i o n C o n v e n t i o n f o r t h e Goodman J a c k 25 9 . S c h e m a t i c I l l u s t r a t i o n o f a P l a t e L o a d i n g T e s t 28 1 0 . R e l a t i o n s h i p Between C o n s t a n t i n E q u a t i o n (2) and P o i s s o n ' s R a t i o . . . 34 1 1 . Modu lus D e f i n i t i o n s f o r P l a t e L o a d i n g T e s t s 39 1 2 . Modulus D e f i n i t i o n s f o r L a b o r a t o r y and Goodman J a c k T e s t s 40 1 3 . S t r e s s - S t r a i n Cu rve f o r A luminum Sample 43 14 . S t r e s s - S t r a i n C u r v e s f o r Q u a r t z i t e G n e i s s (N6) 46 15 . S t r e s s - S t r a i n C u r v e s f o r Q u a r t z i t e G n e i s s (N23) 47 1 6 . S t r e s s - S t r a i n C u r v e s f o r Q u a r t z i t e G n e i s s (N93) 48 17 . F r e q u e n c y H i s t o g r a m s f o r L a b o r a t o r y T e s t s o f Q u a r t z i t e G n e i s s 50 18 . A n i s o t r o p y D iagrams f o r Q u a r t z i t e G n e i s s 52 x i F i g u r e Page 1 9 . S t r e s s - S t r a i n C u r v e s f o r Q u a r t z F e l d s p a r S c h i s t (N40 s t r i k e ) 54 20. S t r e s s - S t r a i n C u r v e s f o r Q u a r t z F e l d s p a r S c h i s t (N40 d i p ) 55 21. S t r e s s - S t r a i n C u r v e s f o r Q u a r t z F e l d s p a r S c h i s t (N70 s t r i k e ) 56 22. S t r e s s - S t r a i n C u r v e s f o r Q u a r t z F e l d s p a r S c h i s t (N70 d i p ) 57 23. S t r e s s - S t r a i n C u r v e s f o r Q u a r t z F e l d s p a r S c h i s t (N202 s t r i k e ) 58 24. S t r e s s - S t r a i n C u r v e s f o r Q u a r t z F e l d s p a r S c h i s t (N202 d i p ) 59 25. F r e q u e n c y H i s t o g r a m s f o r L a b o r a t o r y T e s t s o f Q u a r t z F e l d s p a r S c h i s t 61 26. ' A n i s o t r o p y D iag ram f o r Q u a r t z F e l d s p a r S c h i s t 63 27. R a t i o , o f E W S T R . K E / E W d 1 p vs F o l i a t i o n A n g l e 64 28. V a r i a t i o n o f E l a s t i c R e c o v e r y w i t h F o l i a t i o n A n g l e 66 29. V a r i a t i o n o f t h e R a t i o E / E w i t h F o l i a t i o n A n g l e W . ? 68 30. S t r e s s - S t r a i n C u r v e s f o r P e g m a t i t e (N31) 69 31. S t r e s s - S t r a i n C u r v e s f o r P e g m a t i t e (N33) 70 32. V a r i a t i o n o f Modulus w i t h U n i t We igh t f o r V a r i o u s Rock Types 72 33. Goodman J a c k Load D e f o r m a t i o n C u r v e s f o r Q u a r t z i t e G n e i s s (NX-2) 78 34. Goodman J a c k Load D e f o r m a t i o n C u r v e s f o r Q u a r t z i t e G n e i s s (NX-7) . . . . . . . 79 35. Goodman J a c k Load D e f o r m a t i o n C u r v e s f o r Q u a r t z i t e G n e i s s (NX-3) 80 x i i F i g u r e Page 36. F r e q u e n c y H i s t o g r a m s f o r Goodman J a c k T e s t s i n Q u a r t z i t e G n e i s s 81 37. A n i s o t r o p y o f . t h e Q u a r t z i t e G n e i s s as R e f l e c t e d by t h e Goodman J a c k 83 38. Goodman J a c k Load D e f o r m a t i o n C u r v e s f o r Q u a r t z F e l d s p a r S c h i s t (NXrl2,' 70.0 f t ) 85 39. Goodman J a c k Load D e f o r m a t i o n C u r v e s f o r Q u a r t z F e l d s p a r S c h i s t (NX -12 , 75.0 f t ) 86 40. Goodman J a c k Load D e f o r m a t i o n C u r v e s f o r Q u a r t z F e l d s p a r S c h i s t (NX -20 , 70.0 f t ) 87 41. F r e q u e n c y H i s t o g r a m s f o r Goodman J a c k T e s t s i n Q u a r t z F e l d s p a r S c h i s t ( F i r s t and S e c o n d C y c l e s ) . . . . 89 42. F r e q u e n c y H i s t o g r a m s f o r Goodman J a c k T e s t s i n Q u a r t z F e l d s p a r S c h i s t ( T h i r d C y c l e ) 90 43. F r e q u e n c y D i s t r i b u t i o n o f Second C y c l e W o r k i n g Modulus f o r Q u a r t z F e l d s p a r S c h i s t 91 44. A n i s o t r o p y o f t h e Q u a r t z F e l d s p a r S c h i s t as R e f l e c t e d by t h e Goodman J a c k 93 45. T h r e e P o s s i b l e O r i e n t a t i o n s o f t h e Goodman J a c k w i t h R e s p e c t t o t h e D i r e c t i o n o f L o a d i n g and F o l i a t i o n P l a n e 94 46. Goodman J a c k Load D e f o r m a t i o n Curve f o r P e g m a t i t e . . . 97 47. Load D e f o r m a t i o n Curve f o r Q u a r t z i t e G n e i s s f r o m P l a t e L o a d i n g T e s t . . . .. . 103 48. Load D e f o r m a t i o n Cu rve f o r Q u a r t z F e l d s p a r S c h i s t f r o m P l a t e L o a d i n g T e s t . . . 104 49. F r e q u e n c y D i s t r i b u t i o n f o r t h e P l a t e L o a d i n g T e s t s 106 50. Modu lus Range f o r V a r i o u s T e s t i n g Methods 109 1 CHAPTER I INTRODUCTION A knowledge o f d e f o r m a t i o n p r o p e r t i e s i s r e q u i r e d f o r e n g i n e e r -i n g p r o j e c t s f o u n d e d upon o r e x c a v a t e d w i t h i n r o c k . The d e f o r m a t i o n p r o p e r t i e s a r e used e i t h e r t o p r e d i c t r o c k movement under p r o t o t y p e l o a d i n g o r t o d e v e l o p f i n i t e e l e m e n t mode ls f o r t h e p r o j e c t s i t e . F o r most e n g i n e e r i n g m a t e r i a l s Y o u n g ' s M o d u l u s , a l s o known as t h e modulus o f e l a s t i c i t y , i s used as t h e c h a r a c t e r i s t i c d e f o r m a t i o n p r o p e r t y . T h i s modulus i s a p p l i c a b l e t o m a t e r i a l s w h i c h a r e homogeneous, i s o t r o p i c and e l a s t i c . U n f o r t u n a t e l y , r o c k w i t h i t s g e o l o g i c d e f e c t s s u c h as f r a c t u r e s and j o i n t s i s v e r y s e l d o m homogeneous, i s o t r o p i c o r e l a s t i c . T h u s , t h e modulus o f d e f o r m a t i o n has been d e f i n e d t o i n c l u d e b o t h t h e e l a s t i c d e f o r m a t i o n o f t h e r o c k s u b s t a n c e and t h e d e f o r m a t i o n due t o r o c k d e f e c t s . [ K r u s e , 1 ] The d e f o r m a t i o n m o d u l u s , due t o i t s i n c l u s i v e d e f i n i t i o n , s u f f e r s an i n t r i n s i c p r o b l e m i n i t s d e t e r m i n a t i o n , namely t h e s c a l e e f f e c t . T h a t i s , t e s t s w h i c h i n f l u e n c e a s m a l l e r vo lume o f r o c k t e n d t o have l a r g e r modulus v a l u e s . The r e a s o n b e i n g t h a t s m a l l s c a l e t e s t s do n o t i n f l u e n c e a r e p r e s e n t a t i v e samp le o f t h e more d e f o r m a b l e r o c k d e f e c t s . [ S t a g g and Z i e n k i e w i c z , 2 ] D e f o r m a t i o n modulus v a l u e s c a n v a r y by g r e a t e r t h a n 100% d e p e n d i n g on t h e t e s t i n g method . [ B u k o v a n s k y , 3 ] 2 T h i s t h e s i s examines t h e p r o b l e m o f v a r i a t i o n i n modulus r e s u l t s due t o t e s t i n g method . T h i s i s a c c o m p l i s h e d by c r i t i c a l l y exam-i n i n g t h e r e s u l t s o f t h r e e t e s t i n g m e t h o d s : 1 . L a b o r a t o r y t e s t s c a r r i e d o u t on s a m p l e s o f r o c k c o r e , 2 . Goodman J a c k t e s t s , 3 . P l a t e l o a d i n g t e s t s . The methods a r e compared on t h e b a s i s o f how t h e y r e f l e c t t h e d e f o r m a t i o n b e h a v i o r o f d i s t i n c t r o c k t y p e s . C o n c l u s i o n s a r e t h e n r e a c h e d on the r e l a t i v e m e r i t s o f e a c h method . The e q u i p m e n t , p r o c e d u r e s and t h e o r e t i c a l f o r m u l a t i o n f o r each t e s t i n g method a r e p r e s e n t e d i n d e t a i l . The r e a s o n f o r t h i s i s t h a t t e s t i n g methods i n t h e f i e l d o f r o c k m e c h a n i c s have no t been h i g h l y s t a n d a r d i z e d . Thus any f a c t o r s t h a t can a f f e c t t e s t r e s u l t s s h o u l d a t l e a s t be s p e c i f i e d . 3 CHAPTER I I BACKGROUND TO TESTING PROGRAMMES The in situ t e s t i n g programmes i n t h i s r e p o r t were c a r r i e d o u t a t t h e s i t e o f a p r o p o s e d u n d e r g r o u n d c i v i l e n g i n e e r i n g p r o j e c t . Due t o t h e c o n s i d e r a b l e s i z e o f t h i s p r o j e c t and b e c a u s e o f t h e v a r i a t i o n s i n l o a d c o n c e n t r a t i o n , s e v e r a l t e s t i n g programmes were c a r r i e d o u t t o d e t e r m i n e t h e in situ r o c k b e h a v i o r . The Goodman J a c k programme, i n w h i c h t h e w r i t e r p a r t i c i p a t e d , was c a r r i e d o u t t o d e t e r m i n e d e f o r m a t i o n c h a r a c t e r i s t i c s a t a l a r g e , and t h e r e f o r e s t a t i s -t i c a l l y r e p r e s e n t a t i v e , number o f t e s t l o c a t i o n s . On t h e o t h e r h a n d , t h e p l a t e l o a d i n g t e s t s were p e r f o r m e d a t f e w e r s i t e s b u t t h e vo lume o f r o c k t e s t e d i t s u p p o s e d l y more r e p r e s e n t a t i v e o f in situ r o c k b e h a v i o r . The p l a t e l o a d i n g t e s t s were c a r r i e d o u t by an e n g i n e e r i n g f i r m . The l a b o r a t o r y t e s t s a r e t h e l e a s t r e p r e s e n t a t i v e o f in situ r o c k b e h a v i o u r due t o t h e f a c t t h a t r o c k d e f e c t s a r e ' l o s t i n t h e s a m p l i n g p r o c e s s . In s p i t e o f t h i s i n h e r e n t d i s a d v a n t a g e , l a b o r a t o r y t e s t s a r e p e r f o r m e d f o r a number o f r e a s o n s . F i r s t l y , t h e t e s t i n g i s c o n v e n i e n t t o p e r f o r m . S e c o n d l y , c o n t r o l o f t e s t v a r i a b l e s i s more e a s i l y a t t a i n e d . The t h i r d r e a s o n , t h e most i m p o r t a n t f r o m t h e v i e w p o i n t o f t h i s r e p o r t , i s t h a t l a b o r a t o r y r e s u l t s e s t a b l i s h an u p p e r l i m i t f o r t h e modu lus r e s u l t s f rom t h e in situ t e s t i n g . [ S t a g g and Z i e n k i e w i c z , 2 ] 4 CHAPTER I I I DESCRIPTION OF TEST S ITE A . I n t r o d u c t i o n As p r e v i o u s l y m e n t i o n e d t h e in situ t e s t i n g programmes were c a r r i e d o u t a t t h e s i t e o f a p r o p o s e d u n d e r g r o u n d c o m p l e x . The p r i n c i p a l e x c a v a t i o n i s t o be s e v e r a l hundred f e e t i n l e n g t h . I n a d d i t i o n s e v e r a l s m a l l e r chambers and t u n n e l s a r e t o be e x c a v a t e d . The in situ t e s t s were c a r r i e d o u t i n an e x p l o r a t o r y d r i f t a t t h e p r o j e c t s i t e . T h i s d r i f t had a l e n g t h j u s t o v e r 2100 f e e t and i t s normal c r o s s - s e c t i o n was 7 f e e t by 8 f e e t . T h r e e l a r g e r chambers p r o v i d e d s i t e s f o r p o r t i o n s o f t h e t e s t i n g programmes. B. G e o l o g y o f t h e T e s t S i t e The r o c k s e q u e n c e i n t h e p r o j e c t a r e a c o n s i s t s o f r e g i o n a l l y f o l d e d metamorphosed s e d i m e n t s d i p p i n g a t 10 t o 35 d e g r e e s . The p r i n c i p a l r o c k t y p e s a r e medium t o c o a r s e c r y s t a l l i n e q u a r t z f e l d s p a r s c h i s t s , q u a r t z i t e s , q u a r t z i t e g n e i s s e s w i t h some m i c a s c h i s t s and m i n o r m a r b l e b e d s . The p r i n c i p a l r o c k t y p e s o c c u r as i n t e r b e d d e d u n i t s v a r y i n g f r o m 15 t o 150 f e e t i n t h i c k n e s s . I n a d d i t i o n t o t h e above f o u r r o c k t y p e s , l e n s e s and v e i n s o f p e g m a t i t e and q u a r t z a r e common i n t h e l a y e r e d s e q u e n c e and a r e g e n e r a l l y c o m f o r m a b l e t o t h e l a y e r i n g . 5 An e x a m i n a t i o n o f hand s i z e r o c k s p e c i m e n s i n d i c a t e d t h e p e r c e n t a g e m i n e r a l c o n s t i t u e n t s a s f o l l o w s : Q u a r t z i t e Q u a r t z P e g m a t i t e G n e i s s F e l d s p a r S c h i s t q u a r t z , 55 - 65% q u a r t z , 20 -30% q u a r t z , 80 -90% f e l d s p a r , 20 -25% f e l d s p a r , 10 -20% m u s c o v i t e , 10-20% b i o t i t e , 5-10% b i o t i t e , 30 -40% g a r n e t , m i n o r g a r n e t , m i n o r t o 5% m u s c o v i t e , 10 -20% c h l o r i t e , v e r y m i n o r The q u a r t z i t e g n e i s s s a m p l e s were composed o f u n i f o r m , medium s i z e d m i n e r a l g r a i n s . In most samp les p r e f e r e n t i a l o r i e n t a t i o n o f g r a i n s was n o t p r e s e n t , h o w e v e r , a s m a l l number o f samp les d i d c o n t a i n f a i n t l y o r i e n t e d m i c a c e o u s m i n e r a l s . Many g n e i s s s a m p l e s c o n t a i n e d c h l o r i t i z e d bands and v e r y few c o n t a i n e d h e a l e d f r a c t u r e p l a n e s . The p e g m a t i t e s a m p l e s c o n t a i n e d c o a r s e l y c r y s t a l l i n e q u a r t z and m i c a and d i s p l a y e d no v i s i b l e s t r u c t u r a l f e a t u r e s o r f a b r i c o r i e n t a t i o n . The f o l i a t i o n s p a c i n g i n t h e s c h i s t measu red 1 / 1 6 t o 1 / 8 i n c h . The s c h i s t s a m p l e s showed some d e v i a t i o n i n m i n e r a l c o n t e n t b u t were s e l e c t e d i n o r d e r t h a t a r e p r e s e n t a t i v e s a m p l e o f f o l i a t i o n a n g l e s c o u l d be t e s t e d . F o r t h i s t h e s i s r o c k t y p e s i d e n t i f i e d i n t h e f i e l d as q u a r t z i t e and q u a r t z i t e g n e i s s have been g r o u p e d t o g e t h e r . I t i s r e c o g n i z e d t h a t t h i s g r o u p i n g i s n o t s t r i c t l y v a l i d i n t h e g e o l o g i c s e n s e as q u a r t z i t e g n e i s s i m p l i e s a f o l i a t e d s t r u c t u r e w h e r e a s q u a r t z i t e 5a does n o t . S i n c e i n t h e r o c k c o r e a v a i l a b l e , t h e o n l y c l u e t o f o l i a t e d s t r u c t u r e was the o r i e n t a t i o n o f f i n e g r a i n e d b i o t i t e , t h e p r e s e n c e o f f o l i a t i o n was d i f f i c u l t t o d e t e r m i n e . To a v o i d a r a t h e r a r b i t r a r y d i v i s i o n t h e s i n g l e i n c l u s i v e t e r m q u a r t z i t e g n e i s s was s e l e c t e d . 6 CHAPTER IV REVIEW OF TESTING PROGRAMMES A . L a b o r a t o r y T e s t i n g Programme 1 . Sample P r e p a r a t i o n The l a b o r a t o r y t e s t i n g programme u t i l i z e d s a m p l e s o f BX c o r e . T h i s c o r e was o b t a i n e d f r o m h o l e s d r i l l e d f r o m t h e e x p l o r a t o r y d r i f t i n c o n j u n c t i o n w i t h a s e p a r a t e t e s t i n g programme. From t h e l a r g e f o o t a g e o f c o r e a v a i l a b l e , s a m p l e s were p r e p a r e d t h a t e x h i b i t e d u n i f o r m i t y o f e a c h r o c k t y p e . The c o r e s a m p l e s were d i v i d e d i n t o t h r e e b a s i c r o c k t y p e s ; q u a r t z i t e g n e i s s , p e g m a t i t e and q u a r t z f e l d s p a r s c h i s t . The BX c o r e was c u t w i t h a d iamond saw t o y i e l d s a m p l e s h a v i n g a l e n g t h t o d i a m e t e r r a t i o o f 2 : 1 . The s a m p l e ends were t h e n g r o u n d p a r a l l e l and f l a t u s i n g a \"B lohm S i m p l e x \" s u r f a c e g r i n d e r shown i n F i g u r e 1 . T h i s m a c h i n e i s c a p a b l e o f p r o d u c i n g a s u r f a c e w h i c h i s f l a t t o w i t h i n 50 u i n c h e s , w e l l w i t h i n t h e r e q u i r e d end f l a t n e s s s t a n d a r d . P a r a l l e l i s m o f ends was a s s u r e d by g r i n d i n g b o t h ends o f a g r o u p o f f o u r t e e n s a m p l e s t h e n r e g r i n d i n g t h e f i r s t e n d . A f t e r p r e p a r a t i o n t h e s a m p l e s were d r i e d a t room t e m p e r a t u r e f o r a t l e a s t two w e e k s . Samples were t h e n measured t h r e e t i m e s f o r l e n g t h and t h r e e t i m e s f o r d i a m e t e r and w e i g h e d t o t h e n e a r e s t 0.1 g ram. 7 F i g u r e 1 PREPARATION OF CORE SAMPLES USING \"BLOHM SIMPLEX\" SURFACE GRINDER 8 2 . Load Measurement A x i a l l o a d s were a p p l i e d t o t h e s a m p l e s u s i n g a h y d r a u l i c p r e s s as shown i n F i g u r e 2 . T h i s p r e s s c a n d e v e l o p up t o 2 5 0 , 0 0 0 pounds l o a d b u t f o r t h i s t e s t i n g programme maximum l o a d s were a p p r o x -i m a t e l y 20% o f c a p a c i t y . The l o a d s were measured w i t h a 5 0 , 0 0 0 pound c a p a c i t y , \" B a l d w i n S R - 4 , \" l o a d c e l l . The r e a d o u t u n i t c o n s i s t e d o f a \" D o r i c \" d i g i t a l s t r a i n gauge t r a n s d u c e r u n i t h a v i n g a r e a d i n g c a p a c i t y o f 2 0 , 0 0 0 u n i t s . The c a l i b r a t i o n o f t h e t e s t i n g a s s e m b l y was c a r r i e d o u t u s i n g a \" M o r e h o u s e \" p r o v i n g r i n g mounted i n s e r i e s w i t h t h e l o a d c e l l as shown i n F i g u r e 3 . The \" D o r i c \" t r a n s d u c e r u n i t was a d j u s t e d t o d i s p l a y a number o f u n i t s e q u a l t o t h e a c c u r a t e l y known m e c h a n i c a l l o a d . Thus t h e \" D o r i c \" r e a d d i r e c t l y i n p o u n d s . The l o a d c e l l and \" D o r i c \" a l s o showed l i n e a r i t y o v e r t h e l o a d r a n g e o f t h e p r o v i n g r i n g . The c a l i b r a t i o n p r o v e d t o be e x t r e m e l y s t a b l e o v e r t h e one month d u r a t i o n o f t h e t e s t i n g . S u b s e q u e n t c a l i b r a t i o n c h e c k s c a r r i e d o u t w e e k l y i n d i c a t e d a maximum d e v i a t i o n o f 10 pounds i n 5000 pounds o r 0 .2%. The s e n s i t i v i t y o f t h e h y d r a u l i c p r e s s c o n t r o l s and t h e l o a d s e n s i n g s y s t e m i s i l l u s t r a t e d by t h e f a c t t h a t f o r w e a k e r r o c k t y p e s i t was p o s s i b l e t o a p p l y l o a d i n c r e m e n t s as low as 40 p o u n d s . An a d d i t i o n a l f e a t u r e o f t h e \" D o r i c \" a l l o w e d t h e l o a d i n g r a t e t o be c o n t r o l l e d q u i t e a c c u r a t e l y . The \" D o r i c \" was s e t t o t h e t r a c k mode so t h a t t h e l o a d was s e n s e d a t a p r e c i s e s c a n r a t e . By d e t e r m i n -i n g t h i s s c a n r a t e and by a d j u s t i n g t h e c o n t r o l v a l v e s o f t h e p r e s s t h e d e s i r e d l o a d i n g r a t e c o u l d be a c h i e v e d . F o r e x a m p l e , t h e s c a n r a t e o f 9 F i g u r e 2 HYDRAULIC PRESS AND INSTRUMENTATION FOR LABORATORY TESTING F i g u r e 3 CALIBRATION OF LOAD CELL AND READOUT UNIT n t h e \" D o r i c \" was 0 . 9 0 p e r s e c o n d so t h a t l o a d jumps o f 100 pounds c o r r e s p o n d e d t o a s t r e s s r a t e o f 60 pounds p e r s q u a r e i n c h ( p s i ) / s e c o n d f o r t h e BX c o r e s a m p l e s . 3 . S t r a i n Measurement S t r a i n s were s e n s e d by r e s i s t a n c e t y p e s t r a i n g a u g e s . The s p e c i f i c b r a n d was \" K y o w a , \" t y p e K F C - 5 - C 1 - 1 1 , t h e s p e c i f i c a t i o n s o f w h i c h a r e as f o l l o w s : t y p e : f o i l gauge f a c t o r : 2 . 1 2 ± 1.5% gauge l e n g t h : 5mm t h e r m a l o u t p u t : ±1.8 m i c r o s t r a i n s / d e g r e e c e n t i g r a d e r e s i s t a n c e : 1 2 0 . 0 ± 0 . 3 ohms Due t o t h e l a r g e number o f gauges r e q u i r e d , p r i m a r y c o n s i d e r a t i o n s i n t h e c h o i c e o f gauge t y p e were t h e i r a v a i l a b i l i t y and c o s t . In s p i t e o f t h e l o w c o s t o f t h e s e g a u g e s t h e y were c o n s i d e r e d s a t i s f a c t o r y f o r t h e f o l l o w i n g r e a s o n s : 1 . A l l t e s t i n g was c a r r i e d o u t under l a b o r a t o r y c o n d i t i o n s , t h u s c o m p e n s a t i o n f o r t e m p e r a t u r e e x t r e m e s was u n n e c e s s a r y . 2 . S t r a i n s were o f r e l a t i v e l y s m a l l m a g n i t u d e ( l e s s t h a n 1%). 3 . O n l y 2 o r 3 l o a d i n g c y c l e s were e m p l o y e d , t h e r e f o r e t h e f a t i g u e l i f e o f t h e gauge was u n i m p o r t a n t . 12 4 . Hea t d i s s i p a t i o n was no p r o b l e m s i n c e t h e gauge c u r r e n t w o u l d be 6 . 2 5 m i l l i - a m p e r e s , f a r l e s s t h a n t h e 100 m i l l i -ampere maximum f o r f o i l t y p e g a u g e s . [ D a l l e y and R i l e y , 4 ] 5 . The gauge l e n g t h o f 5 mm was c o n s i d e r e d s u f f i c i e n t l y l o n g , (a) t o a v o i d t h e s t r a i n gauge b e i n g a t t a c h e d t o a s i n g l e r o c k g r a i n , and (b) t o a v o i d s t a b i l i t y p r o b l e m s due t o s t r e s s r e l a x a t i o n i n the a d h e s i v e . Two a x i a l and two c i r c u m f e r e n t i a l s t r a i n gauges were a t t a c h e d t o t h e g n e i s s and p e g m a t i t e s a m p l e s . S i n c e t h e s e r o c k t y p e s were u n i f o r m and u n f o l i a t e d t h e gauges were n o t o r i e n t e d w i t h r e s p e c t t o s t r u c t u r a l f e a t u r e s . F i g u r e 4 shows gauge i n s t a l l a t i o n s on t h e v a r i o u s r o c k t y p e s . B e c a u s e o f t h e d i s t i n c t f o l i a t i o n p r e s e n t i n t h e s c h i s t samp les f o u r a x i a l gauges were used i n an a t t e m p t t o d e t e c t d i r e c t i o n a l movements. The p o s i t i o n o f t h e s e gauges w i t h r e s p e c t t o t h e s t r i k e and d i p d i r e c t i o n s o f t h e f o l i a t i o n i s i l l u s t r a t e d i n F i g u r e 5 . The p r o c e d u r e f o r a t t a c h i n g t h e s t r a i n gauges t o t h e r o c k s a m p l e s was t h a t g i v e n by Hardy [ 5 ] w i t h some m o d i f i c a t i o n s . T h i s p r o c e d u r e c a n be summar i zed as f o l l o w s : 1 . A f t e r c u t t i n g and g r i n d i n g , samp les d r i e d a t room t e m p e r a t u r e f o r n o t l e s s t h a n two w e e k s . 2 . The s a m p l e s were c l e a n e d o f a l l d i r t and g r e a s e . 3 . P o s i t i o n i n g l i n e s were drawn a x i a l l y and c i r c u m f e r e n t i a l l y a t m i d - h e i g h t t o l o c a t e g a u g e s . DEPLOYMENT OF STRAIN GAUGES FOR THE THREE ROCK TYPES From l e f t t o r i g h t ; q u a r t z i t e g n e i s s , p e g m a t i t e , q u a r t z f e l d s p a r s c h i s t F i g u r e 5 PLACEMENT OF STRAIN GAUGES RELATIVE TO STRIKE AND DIP DIRECTIONS FOR QUARTZ FELDSPAR SCHIST SAMPLES The a r e a s t o w h i c h gauges were t o be a t t a c h e d were t h o r o u g h l y c l e a n e d as f o l l o w s : (a ) a c e t o n e v i g o r o u s l y b r u s h e d i n u s i n g a t o o t h b r u s h , (b) f i n a l c l e a n i n g u s i n g t i s s u e p a p e r s o a k e d i n a c e t o n e . The s a m p l e was a l l o w e d t o d r y u n t i l a l l t r a c e s o f a c e t o n e had d i s a p p e a r e d , ( a b o u t 2 m i n u t e s ) Two s t r a i n gauges were removed f r o m t h e i r p a c k a g e s , s p e c i a l c a r e b e i n g t a k e n n o t t o t o u c h t h e u n d e r s i d e o f t h e gauge . The c e m e n t ( P h i 1 1 i p s - T y p e P R 9 2 4 4 / 0 4 ) was m i x e d and a p p l i e d t o two o f t h e gauge p o s i t i o n s on t h e r o c k s a m p l e . The gauge was p l a c e d on t h e samp le i n t h e c o r r e c t o r i e n t a t i o n . A p i e c e o f c e l l o p h a n e was p l a c e d o v e r t h e gauge and any b u b b l e s i n t h e cement were removed by p r e s s i n g w i t h t h e thumb. The s a m p l e , w i t h i t s two a t t a c h e d g a u g e s , w a s p l a c e d i n a d r y i n g p r e s s c o n s i s t i n g o f wooden b l o c k s , sponge r u b b e r and a G - c l a m p . The cement was a l l o w e d t o s e t f o r 5 m i n u t e s w i t h t h e sample i n t h e gauge p r e s s . The sample was t h e n w i t h d r a w n , t h e c e l l o -phane r e m o v e d , and s t e p s 5 t o 10 r e p e a t e d f o r t h e s e c o n d s e t o f g a u g e s . The sample was a l l o w e d t o d r y f o r an a d d i t i o n a l 24 hou rs t o e n s u r e c o m p l e t e cement c u r i n g . T e r m i n a l t a b s were cemented t o t h e s a m p l e t o p r o v i d e a s o l d e r i n g p o i n t f o r a t t a c h i n g gauge l e a d w i r e s and c i r c u i t l e a d w i r e . A f t e r s o l d e r i n g l e a d s was c o m p l e t e t h e c o n t i n u i t y o f t h e gauge c i r c u i t was c h e c k e d u s i n g an o h m e t e r . 16 14 . The gauges and s o l d e r j o i n t s were c o a t e d w i t h a l o w modulus s i l i c o n e r u b b e r . T h e r e were s e v e r a l r e a s o n s f o r t h i s p r e c a u t i o n . F i r s t l y , t o p r o t e c t t h e gauge i n s t a l l a t i o n f rom m o i s t u r e \" i n t h e a i r . S e c o n d l y , t o f i r m l y a t t a c h t h e l e a d w i r e s t o t h e samp le t o p r e v e n t any i n d u c e d s t r a i n t o t h e g a u g e s . F i n a l l y , t o p r e v e n t t h e l e a d w i r e s f r o m b e i n g p u l l e d o f f . The r e a d o u t u n i t s f o r s t r a i n s c o n s i s t e d o f two c o m m e r c i a l b r i d g e s t h a t were c a l i b r a t e d t o r e a d s t r a i n d i r e c t l y i n m»icroinches p e r i n c h . The a x i a l s t r a i n s were r e a d o u t on a \"Budd S t r a i n I n d i c a t o r \" w h i l e a \"BLH S t r a i n I n d i c a t o r \" was used f o r c i r c u m f e r e n t i a l s t r a i n s o r a x i a l s t r a i n s i n t h e d i p d i r e c t i o n i n t h e c a s e o f s c h i s t s a m p l e s . The s t r a i n gauge c i r c u i t f o r e a c h s e t o f gauges i s i l l u s t r a t e d i n A p p e n d i x 1 . The c i r c u i t i n d i c a t e s d o u b l e t h e c o r r e c t s t r a i n , t h e p r o o f o f w h i c h i s a l s o shown i n A p p e n d i x 1 . T h u s , s t r a i n s were d e t e c t e d t o t h e n e a r e s t 0.5 m i c r o i n c h / i n c h . T e m p e r a t u r e f l u c t u a t i o n s , t hough m i n i m a l u n d e r l a b o r a t o r y c o n -d i t i o n s , were compensated f o r i n t h e s t r a i n gauge c i r c u i t r y . S t r a i n gauges were a t t a c h e d t o a \"dummy\" r o c k sample i n t h e same o r i e n t a t i o n as t h o s e on t h e t e s t s a m p l e s . These gauges were t h e n c o n n e c t e d as compen-s a t i n g gauges i n t h e s t r a i n gauge c i r c u i t . A t e m p e r a t u r e change w o u l d c a u s e e q u a l t h e r m a l s t r a i n s i n t h e t e s t and \"dummy\" s a m p l e s a s s u m i n g t h e i r c o e f f i c i e n t s o f t h e r m a l e x p a n s i o n t o be t h e same. However , due t o t h e p o s i t i o n s o f t h e gauges i n t h e c i r c u i t t h e e l e c t r i c a l o u t p u t o f t h e t e s t and \"dummy\" s a m p l e s w o u l d be i d e n t i c a l b u t o f o p p o s i t e s i g n . The e l e c t r i c a l e f f e c t o f t h e t h e r m a l s t r a i n s was t h e r e b y c a n c e l l e d . 17 4 . T e s t P r o c e d u r e The t e s t p r o c e d u r e f o r t h e l a b o r a t o r y r o c k t e s t i n g can be summar-i z e d as f o l l o w s : 1 . The \" D o r i c \" was a l l o w e d t o warm up u n t i l i t showed t h e c o r r e c t z e r o r e a d i n g . 2 . The samp le was s e t i n t h e p r e s s and c o n n e c t e d t o t h e b r i d g e c i r c u i t s . A f t e r a warmup p e r i o d t h e z e r o r e a d i n g s were t a k e n . 3 . From p r e v i o u s s t r e n g t h t e s t i n g programmes an e s t i m a t e o f t h e u l t i m a t e c o m p r e s s i v e s t r e n g t h was made. 4 . The samp le was t h e n i n c r e m e n t a l l y l o a d e d t o 75% o f t h e e s t i m a t e d u l t i m a t e c o m p r e s s i v e s t r e n g t h . The l o a d i n c r e m e n t s were c h o s e n s u c h t h a t a c o m p l e t e l o a d - u n l o a d c y c l e had 15 t o 20 r e a d i n g s . 5 . The maximum l o a d a n d / o r l o a d i n c r e m e n t s were m o d i f i e d on s e c o n d and s u b s e q u e n t l o a d i n g c y c l e s i f w a r r a n t e d by t h e f i r s t c y c l e b e h a v i o u r . F o r e x a m p l e , i f t h e f i r s t c y c l e s t r a i n r e a d i n g s showed l i n e a r i t y t h e n t h e maximum l o a d and l o a d i n c r e m e n t s w o u l d be i n c r e a s e d on t h e s e c o n d c y c l e . S e v e r a l p r o b l e m s a r o s e i n c o n j u n c t i o n w i t h t h e t e s t i n g programme. The most i m p o r t a n t o f t h e s e was t h a t i t was i m p e r a t i v e t h a t t h e t e s t i n g be n o n - d e s t r u c t i v e i n o r d e r t h a t o t h e r w o r k e r s c o u l d c a r r y o u t f u r t h e r t e s t i n g on t h e s a m p l e s . Out o f a t o t a l o f 72 samp les t e s t e d , 11 were b r o k e n , due m a i n l y t o o v e r e s t i m a t i n g t h e s t r e n g t h o r t o d i f f i c u l t i e s e n c o u n t e r e d when i n i t i a t i n g l o w l o a d i n g r a t e s a t sample l o a d s above 3 0 , 0 0 0 p o u n d s . A s e c o n d p r o b l e m i n v o l v e d l o s s o f l o a d due t o l e a k a g e i n t h e c o n t r o l v a l v e s o f t h e p r e s s . T h i s c o n d i t i o n was most p r e v a l e n t a t l ow 18 l o a d s on t h e u n l o a d i n g c y c l e and was overcome by s y n c h r o n i z i n g t h e s t r a i n r e a d i n g s w i t h t h e d r i f t i n g l o a d . 5 . Summary When c o m p a r i n g t h e r e s u l t s o f t e s t i n g t e c h n i q u e s i t i s d e s i r a b l e t o make t h e s e c o m p a r i s o n s w i t h r e s p e c t t o t h e t i m e r e q u i r e d t o c a r r y o u t t h e t e s t i n g . A p p e n d i x 2 p r e s e n t s a t i m e s t u d y f o r e a c h phase o f t h e l a b o r a t o r y t e s t i n g programme f r o m t h e t i m e t h e c o r e i s r e c e i v e d a t t h e l a b o r a t o r y . I t i s e m p h a s i z e d t h a t t h e s e t i m e s a r e t h o s e e n c o u n t e r e d by t h i s w r i t e r . The t i m e s r e q u i r e d by a t e s t i n g l a b o r a t o r y w o u l d u n d o u b t a b l y be l e s s . From A p p e n d i x 2 i t i s s e e n t h a t samp le p r e p a r a t i o n and t e s t i n g r e q u i r e d 1 3 / 4 h o u r s p e r s a m p l e . C l a r k e [ 6 ] p r e s e n t e d a t a b l e o f i t e m s w h i c h s h o u l d be s p e c i f i e d f o r l a b o r a t o r y t e s t s f o r d e f o r m a t i o n m o d u l u s . Based on t h a t t a b l e , a summary o f t h e t e s t i t e m s u t i l i z e d i n t h e w r i t e r ' s t e s t programme i s p r e s e n t e d i n T a b l e 1 . B. Goodman J a c k T e s t i n g 1 . D e s c r i p t i o n o f Equ ipment The Goodman J a c k , a l s o r e f e r r e d t o as t h e NX p l a t e b e a r i n g d e v i c e o r b o r e h o l e j a c k , i s a h y d r a u l i c j a c k d e s i g n e d t o d e t e r m i n e t h e l o a d - d e f o r m a t i o n c h a r a c t e r i s t i c s o f r o c k . T h i s i s a c c o m p l i s h e d by a p p l y i n g a u n i d i r e c t i o n a l l o a d t o a p o r t i o n o f t h e c i r c u m f e r e n c e o f an NX b o r e h o l e by f o r c i n g a p a r t r i g i d b e a r i n g p l a t e s . The d i s a s s e m b l e d j a c k i s shown i n F i g u r e 6 . As can be s e e n , i t c o n s i s t s o f two s t e e l p l a t e s w h i c h a r e f o r c e d a p a r t by 12 r a c e t r a c k -TABLE 1 SUMMARY OF LABORATORY TESTING PROGRAMME 19 1. L e n g t h o f S a m p l e : a v e r a g e 3 . 2 0 0 i n c h e s 2 . D i a m e t e r o f S a m p l e : a v e r a g e 1 . 6 0 0 i n c h e s 3 . Shape o f S a m p l e : C r o s s - s e c t i o n : c i r c u l a r V e r t i c a l s e c t i o n : r e c t a n g u l a r Symmetry : t h a t o f a r i g h t c y c l i n d e r 4 . End C o n d i t i o n s : P l a t e n : h a r d e n e d s t e e l S p e c i m e n : f l a t t o w i t h i n 0 .001 i n c h L u b r i c a n t : none 5 . Measurement o f L o a d : l o a d c e l l c o u p l e d t o a d i g i t a l r e a d o u t u n i t 6 . R a t e o f L o a d i n g : G n e i s s , P e g m a t i t e : 60 p s i / s e c S c h i s t : 30 p s i / s e c 7. Number o f C y c l e s : 2 ( o c c a s i o n a l l y 3) 8 . T e s t t o F a i l u r e : no 9 . S e n s o r s : R e s i s t a n c e s t r a i n gauges T y p e : f o i l L e n g t h : 5mm Number: 4 P l a c e m e n t : g n e i s s , p e g m a t i t e : 2 a x i a l , 2 c i r c u m f e r e n t i a l s c h i s t : 4 a x i a l 1 0 . L a t e r a l E x t e n s i o n - P o i s s o n ' s R a t i o : measured c i r c u m f e r e n t i a l l y w i t h s t r a i n gauges 1 1 . C o o r d i n a t i o n o f above w i t h r o c k p r o p e r t i e s : R a t i o gauge l e n g t h t o g r a i n s i z e : g n e i s s 1 0 : 1 , p e g m a t i t e 2 : 1 , s c h i s t 5:1 R a t i o sample s i z e t o g r a i n s i z e : g n e i s s 1 6 0 : 1 , p e g m a t i t e 4 0 : 1 , s c h i s t 80 :1 1 2 . I n s t r u m e n t a t i o n : A c c u r a c y : l o a d : - 10 l b . i n 5000 l b o r 0 .2% s t r a i n : - T e k t r o n i x O s c i l l o s c o p e #549 used as s t a n d a r d O v e r a l l s y s t e m c h e c k e d u s i n g an a luminum s a m p l e . 21 shaped p i s t o n s . Two l i n e a r v a r i a b l e d i f f e r e n t i a l t r a n s f o r m e r s (known as LVDTs) measure t h e d i a m e t r a l d e f o r m a t i o n a t e i t h e r end o f t h e 8 i n c h l o n g p l a t e s . The j a c k i s c o l l a p s e d by means o f two r e t u r n p i s t o n s . The j a c k ' s c o l l a p s e d d i a m e t e r i s 2 3 / 4 i n c h e s , t h e r e b y p r o v i d i n g o n e -q u a r t e r i n c h c l e a r a n c e i n an NX b o r e h o l e . A n c i l l a r y e q u i p m e n t used i n c o n j u n c t i o n w i t h t h e Goodman J a c k i n c l u d e s a p o r t a b l e t r a n s d u c e r r e a d o u t u n i t , h y d r a u l i c pump, p r e s s u r e g a u g e , h y d r a u l i c hose and e l e c t r i c a l c a b l e . The t r a n s d u c e r r e a d o u t i s c a l i b r a t e d by p l o t t i n g r e a d i n g s on t h i s u n i t v e r s u s t h e d i a m e t e r o f t h e j a c k . The h y d r a u l i c pump i s hand o p e r a t e d t o p r o d u c e 1 0 , 0 0 0 p s i l i n e p r e s s u r e . The a s s e m b l e d j a c k , t r a n s d u c e r r e a d o u t u n i t and h y d r a u l i c pump a r e shown i n F i g u r e 7. The o p e r a t i n g s p e c i f i c a t i o n s o f t h e j a c k a r e as f o l l o w s . A maximum h y d r a u l i c l i n e p r e s s u r e o f 1 0 , 0 0 0 p s i p r o d u c e s a s t r e s s o f 9 , 3 0 0 p s i a g a i n s t t h e s i d e s o f t h e b o r e h o l e . T h i s s t r e s s f i e l d i s u n i f o r m and u n i d i r e c t i o n a l and c o r r e s p o n d s t o a f o r c e o f 1 5 8 , 0 0 0 pounds . [ T r a n , 7 ] The j a c k has a 0 . 5 i n c h e x t e n s i o n r a n g e f rom 2 . 7 5 t o 3 . 2 5 i n c h e s i n d i a m e t e r . The LVDTs have a l i n e a r r a n g e o f 0 . 2 i n c h e s . T h i s l i n e a r r a n g e can be a d j u s t e d t o c o r r e s p o n d t o any p o r t i o n o f t h e j a c k e x t e n s i o n r a n g e d e p e n d i n g upon r o c k d e f o r m a b i l i t y . Under normal c o n d i t i o n s t h e l i n e a r r a n g e o f t h e LVDTs c o r r e s p o n d s t o j a c k d i a m e t e r s f r o m 2 . 9 t o 3.1 i n c h e s . B o r e h o l e t e s t m e t h o d s , s u c h as t h e Goodman J a c k , have s e v e r a l a d v a n t a g e s . The p r i n c i p a l a d v a n t a g e i s t h a t s p e c i a l u n d e r -g r o u n d t e s t chambers need n o t be c o n s t r u c t e d . 23 Most p r o j e c t s i n v o l v e l a r g e e x p l o r a t o r y d r i l l i n g p rograms w h i c h p r o v i d e a p p r o p r i a t e t e s t l o c a t i o n s f o r deep i n v e s t i g a t i o n o f u n d i s t u r b e d r o c k u s i n g bo re h o l e m e t h o d s . F u r t h e r a d v a n t a g e s o f t h e s e methods a r e t h a t t h e y c o n s i s t o f r e l a t i v e l y l i g h t e q u i p m e n t and a r e f a s t and e c o n o m i c a l t o c a r r y o u t . As a r e s u l t many t e s t s c a n be run and a s t a t i s t i c a l a v e r a g e e m p l o y e d . Compared t o o t h e r b o r e h o l e methods s u c h as d i l a t o m e t e r s , t h e Goodman J a c k has two d i s t i n c t a d v a n t a g e s . F i r s t l y , t h e j a c k c a n d e v e l o much h i g h e r c o m p r e s s i v e s t r e s s e s ; 9300 p s i v e r s u s 2200 p s i maximum f o r d i l a t o m e t e r s . T h i s means t h a t t h e Goodman J a c k c a n be used t o d e t e r m i n t h e d e f o r m a t i o n modu lus i n v e r y r i g i d r o c k . The s e c o n d a d v a n t a g e i s t h a t t h e j a c k has d i r e c t i o n a l l o a d i n g c a p a b i l i t i e s w h i l e d i l a t o m e t e r s s u p p l y a u n i f o r m i n t e r n a l p r e s s u r e t o a s e c t i o n o f t h e b o r e h o l e . T h u s , t h e j a c k c a n be o r i e n t e d on s p e c i f i c g e o l o g i c f e a t u r e s a s s u m i n g t h e i r i n t e r s e c t i o n w i t h t h e b o r e h o l e i s a c c u r a t e l y known. F o r e x a m p l e , t h e j a c k c a n be p o s i t i o n e d so t h a t i t f o r c e s a p a r t f r a c t u r e s o r j o i n t s p r o v i d e d good bo re h o l e d a t a i s a v a i l a b l e . The d i r e c t i o n a l l o a d i n g c a p a b i l i t y a l s o means t h a t t h e d e f o r m a t i o n modulus c a n be d e t e r m i n e d i n s e v e r a l d i r e c t i o n s t h e r e b y p r o v i d i n g i n f o r m a t i o n on t h e a n i s o t r o p y o f t h e r o c k . 2 . P r o c e d u r e The Goodman J a c k t e s t p r o c e d u r e f o l l o w e d c l o s e l y t h a t recommended by t h e m a n u f a c t u r e r , S l o p e I n d i c a t o r Company. The p r i n c i p a l m o d i f i c a t i o n i n v o l v e d t h e s u b s t i t u t i o n o f i n s e r t i o n r o d s f o r BX c a s i n g t o i n s e r t t h e j a c k i n t o t h e b o r e h o l e . The c a s i n g i s recommended i n o r d e r t o p r o v i d e maximum p r o t e c t i o n f o r t h e j a c k , h y d r a u l i c hoses and e l e c t r i c a l c a b l e s . The d i s a d v a n t a g e o f t h i s s y s t e m i s t h a t t h e c a s i n g w e i g h s a p p r o x i m a t e l y 50 pounds p e r 10 f o o t s e c t i o n . T h u s , f o r l e n g t h s o f c a s i n g g r e a t e r t h a n 20 f e e t , a d r i l l r i g o r s i m i l a r s y s t e m must be used t o h a n d l e t h e l o a d . In o r d e r t o f a c i l i t a t e manual p l a c e m e n t o f t h e j a c k , l i g h t a luminum i n s e r t i o n r o d s were u s e d . These r o d s w e i g h e d l e s s t h a n 5 pounds p e r 10 f o o t s e c t i o n . As a r e s u l t , two men w i t h a s m a l l hand w i n c h c o u l d p l a c e and r e t r i e v e t h e j a c k a t d e p t h s g r e a t e r t h a n 100 f e e t f rom t h e e x p l o r a t o r y d r i f t . The a c t u a l t e s t i n g p r o c e d u r e f o l l o w e d w i t h t h e Goodman J a c k can be summar i zed as f o l l o w s : 1 . H y d r a u l i c hoses and e l e c t r i c a l c a b l e s w e r e c o n n e c t e d . 2 . The j a c k was i n s e r t e d a s h o r t d i s t a n c e i n t o t h e b o r e h o l e , l o a d e d and r e t r a c t e d t o e n s u r e c o r r e c t p e r f o r m a n c e a t d e p t h . 3 . The j a c k was t h e n p o s i t i o n e d a t t h e c o r r e c t d e p t h and o r i e n t e d w i t h r e s p e c t t o t h e d r i f t a x i s . (See F i g u r e 8) 4 . The j a c k was expanded u s i n g t h e hand pump u n t i l a h y d r a u l i c p r e s s u r e o f 1000 p s i was r e a c h e d . T h i s base l o a d i n g was t h e i n i t i a l p o i n t o f t h e l o a d d e f o r m a t i o n d a t a r a t h e r t h a n t h e z e r o s t r e s s p o i n t b e c a u s e o f t h e d i f f i c u l t y i n d e t e r m i n i n g t h e e x a c t moment o f j a c k - b o r e h o l e c o n t a c t . 5 . The j a c k p r e s s u r e was i n c r e a s e d i n i n c r e m e n t s o f 1000 p s i t o a maximum o f 9500 p s i . R e a d i n g s f o r b o t h d e f o r m a t i o n t r a n s d u c e r s were t a k e n a t e a c h l o a d i n c r e m e n t . I f , a t any p o i n t d u r i n g t h e l o a d i n g c y c l e , t h e s e r e a d i n g s d i f f e r e d by more t h a n 0 . 0 2 0 i n c h e s t h e j a c k was r e t r a c t e d and r e - l o c a t e d . 26 The r e a s o n f o r t h i s p r e c a u t i o n was t h a t t h e d i f f e r e n c e i n -d i c a t e d t h e j a c k was t i l t i n g due t o n o n - u n i f o r m d e f o r m a t i o n o f t h e r o c k . E x c e s s i v e t i l t i n g c o u l d c a u s e wear on t h e j a c k ' s g u i d e p i n s o r LVDT a d a p t e r o r , i n t h e e x t r e m e c a s e , c a u s e t h e j a c k t o j a m . 6 . The j a c k p r e s s u r e was t h e n d e c r e a s e d i n i n c r e m e n t s o f 1000 p s i t o c o m p l e t e t h e u n l o a d i n g p o r t i o n o f t h e c y c l e . F o r most l o c a t i o n s 2 o r 3 l o a d - u n l o a d c y c l e s were p e r f o r m e d . However , i n some c a s e s , i n c o n s i s t e n t r e s u l t s n e c e s s i t a t e d 4 c y c l e s . 7 . A f t e r s t e p 6 was c o m p l e t e d t h e j a c k w o u l d be r o t a t e d and s i m i l a r t e s t s c a r r i e d o u t a t 90 d e g r e e s and 45 d e g r e e s t o t h e f i r s t d i r e c t i o n o f l o a d i n g . The l o a d i n g was c o n t r o l l e d by how f a s t t h e o p e r a t o r c o u l d d e v e l o p p r e s s u r e w i t h t h e hand pump. I t i s e s t i m a t e d t h a t t h e l o a d i n g r a t e was a p p r o x i m a t e l y 100 t o 150 p s i p e r s e c o n d ( r o c k p r e s s u r e ) . The t i m e r e q u i r e d f o r a 2 c y c l e t e s t f o r one o r i e n t a t i o n o f j a c k i n g was a p p r o x i m a t e l y 10 t o 20 m i n u t e s d e p e n d i n g on t h e t i m e n e c e s s a r y t o l o c a t e t h e j a c k . The m a i n p r o b l e m e n c o u n t e r e d i n t h e Goodman J a c k t e s t i n g programme c o n c e r n e d t h e t e n d e n c y o f t h e j a c k t o m a l f u n c t i o n i n t h e r e t r a c t o p e r a t i o n . T h i s happened t w i c e d u r i n g t h e c o u r s e o f t h e programme w i t h t h e r e s u l t t h a t t h e j a c k c o u l d no t be r e a d i l y r e t r i e v e d f r o m t h e b o r e h o l e . P o s s i b l e c a u s e s f o r t h e m a l f u n c t i o n i n g i n c l u d e d i s -l o d g e d 0 - r i n g s on t h e r e t r a c t p i s t o n s , mud and r o c k c h i p s e n t e r i n g t h e j a c k and f a i l u r e t o c o m p l e t e l y t i g h t e n t h e s e l f - s e a l i n g h y d r a u l i c c o u p l i n g s . 27 In b o t h c a s e s , a f t e r c o n s i d e r a b l e l o s t t e s t i n g t i m e , t h e j a c k was r e t r i e v e d w i t h t h e a i d o f a d r i l l r i g . A s e c o n d p r o b l e m e n c o u n t e r e d , c o n c e r n e d t h e d e f o r m a t i o n t r a n s -d u c e r s . D u r i n g t h e c o u r s e o f d i s a s s e m b l i n g t h e j a c k i t was f o u n d t h a t t h e r e was a s m a l l amount o f p l a y between t h e LVDTs and t h e i r m o u n t i n g s . T h i s c o n d i t i o n meant t h a t when t h e d i r e c t i o n o f l o a d i n g was r e v e r s e d t h e i n i t i a l j a c k d e f o r m a t i o n w o u l d be l o s t i n t h e b a c k l a s h o f t h e LVDTs. The r e s u l t was t h a t t h e f i r s t p r e s s u r e i n c r e m e n t o f l o a d i n g o r u n l o a d i n g e x h i b i t e d an a b n o r m a l l y h i g h d e f o r m a t i o n m o d u l u s . T h i s e f f e c t i s shown q u i t e c l e a r l y on t h e l o a d - d e f o r m a t i o n c u r v e s and i t w i l l be d i s c u s s e d l a t e r . I t s h o u l d be n o t e d t h a t t h i s was a c h a r a c t e r i s t i c o f t h e s p e c i f i c j a c k b e i n g used and p r o b a b l y i s no t an i n h e r e n t f e a t u r e o f a l l Goodman J a c k s . C. P l a t e L o a d i n g T e s t s 1. D e s c r i p t i o n o f Equ ipment P l a t e l o a d i n g t e s t s a r e p e r f o r m e d t o d e t e r m i n e t h e in situ d e f o r m a t i o n c h a r a c t e r i s t i c s o f a r o c k mass . T h i s i s a c c o m p l i s h e d i n one o f two w a y s . One m e t h o d , known as t h e c a b l e j a c k i n g t e s t , l o a d s a p l a t e on t h e s u r f a c e . The l o a d i s s u p p l i e d by h y d r a u l i c j a c k s , t h e r e a c t i o n b e i n g p r o v i d e d by c a b l e s a n c h o r e d a t d e p t h . [See Z i e n k i e w i c z and S t a g g , 8 ] In t h e s e c o n d method a h y d r a u l i c j a c k i s used t o s e p a r a t e t h e w a l l s o f a t u n n e l . The p l a t e l o a d i n g t e s t s f o r t h i s ; p r o j e c t u t i l i z e d t h e l a t t e r method as i s s c h e m a t i c a l l y shown i n F i g u r e 9 . F o r a d e t a i l e d s t u d y o f t u n n e l p l a t e l o a d i n g t e s t s see W a l l a c e , S l e b i r , e_t a K [ 9 ] . 2 p F i g u r e 9 SCHEMATIC ILLUSTRATION OF A PLATE LOADING TEST 29 As p r e v i o u s l y m e n t i o n e d t h e p l a t e l o a d i n g t e s t s were n o t p e r -fo rmed by t h i s w r i t e r . The f o l l o w i n g i n f o r m a t i o n was s u p p l i e d by t h e company s p o n s o r i n g t h i s r e s e a r c h work and i t r e f e r s t o work c a r r i e d o u t d u r i n g 1967 . P l a t e l o a d i n g t e s t s a t t h i s p r o j e c t were c a r r i e d o u t a t s i x s e p a r a t e l o c a t i o n s i n t h e e x p l o r a t o r y d r i f t g i v i n g t w e l v e c o m p l e t e t e s t s , s i n c e measurements were made a t b o t h ends o f t h e l o a d i n g a s s e m b l y . Loads were a p p l i e d by a 200 t o n ram a c t i n g on 12 i n c h d i a m e t e r c i r c u l a r o r t e n i n c h s q u a r e b e a r i n g p l a t e s . Loads were c a r r i e d t o t h e pads by t e s t beams made f r o m 8 i n c h d i a m e t e r d o u b l e - e x t r a heavy w a l l p i p e . S e c t i o n s o f t h e p i p e i n d i f f e r e n t l e n g t h s c o u l d be b o l t e d t o g e t h e r so t h a t t h e r e q u i r e d d i s t a n c e a c r o s s t h e t u n n e l c o u l d be s p a n n e d . D e f l e c t i o n s were s e n s e d w i t h d i a l g a u g e s , a c c u r a t e t o 0 .0001 i n c h , mounted a g a i n s t t h e b e a r i n g p l a t e s . 2 . P r o c e d u r e The p l a t e l o a d i n g t e s t s were c a r r i e d o u t i n two o r i e n t a t i o n s , v e r t i c a l l y o r h o r i z o n t a l l y a c r o s s t h e t u n n e l . Each t e s t c o n s i s t e d o f f o u r c y c l e s o f l o a d i n g and u n l o a d i n g t h e b e a r i n g s u r f a c e s w i t h p r o g r e s s i v e l y h i g h e r l o a d s and r e c o r d i n g t h e r o c k d e f l e c t i o n s . Ten r e a d i n g s were made d u r i n g each c y c l e o f l o a d i n g and u n l o a d i n g w i t h t h e l o a d h e l d c o n s t a n t f o r 30 m i n u t e s a t t h e maximum and minimum l o a d t o a l l o w t h e r o c k t o a d j u s t . The c y c l e s o f one t e s t c o n s i s t e d o f : 50 t o n s maximum l o a d i n i n c r e m e n t s o f 5 t o n s ; 100 t o n s maximum l o a d i n i n c r e m e n t s o f 10 t o n s ; 150 t o n s maximum l o a d i n i n c r e m e n t s o f 15 t o n s ; and 200 t o n s maximum l o a d i n i n c r e m e n t s o f 20 t o n s . One c o m p l e t e t e s t , t h e n , i n v o l v e d e i g h t y s t e p s and r e q u i r e d s i x t o e i g h t h o u r s . 31 CHAPTER V INTERPRETATION OF TEST DATA A . L a b o r a t o r y T e s t i n g Programme S i n c e l a b o r a t o r y t e s t s a m p l e s have a c o n s i s t e n t g e o m e t r i c shape and a r e s u b j e c t t o a u n i f o r m s t r e s s f i e l d , no t h e o r e t i c a l c o n s i d e r a t i o n s a r e r e q u i r e d t o d e t e r m i n e t h e d e f o r m a t i o n m o d u l u s . In o t h e r w o r d s , t h e d e f o r m a t i o n modulus f o l l o w s d i r e c t l y f rom i t s d e f i n i t i o n . Many w r i t e r s have r e p o r t e d f a c t o r s w h i c h c a n a f f e c t t h e modulus v a l u e d e t e r m i n e d f o r a p a r t i c u l a r s a m p l e . See Hardy [ 5 ] , O b e r t and D u v a l l [ 1 0 ] , Hawkes and M e l l o r [ 11 ] o r S t a g g and Z i e n k i e w i c z [ 2 ] . Some o f t h e s e f a c t o r s i n c l u d e l o a d i n g r a t e , m o i s t u r e c o n t e n t and sample end c o n d i t i o n s . T ime c o n s i d e r a t i o n s p r e v e n t e d a t h o r o u g h s t u d y o f t h e s e f a c t o r s a l t h o u g h t h e work o f o t h e r i n v e s t i g a t o r s s u g g e s t s t h a t t h e y a r e o f c o m p a r a t i v e l y m i n o r s i g n i f i c a n c e . H e n c e , f o r t h i s t h e s i s , t h e i r e f f e c t i s c o n s i d e r e d t o be i n s i g n i f i c a n t . B. Goodman J a c k T e s t i n g The f o r c e a p p l i e d by t h e Goodman J a c k t o t h e b o r e h o l e w a l l s i s u n i d i r e c t i o n a l . Thus a t a l l p o i n t s a l o n g t h e b o r e h o l e w a l l , e x c e p t t h e l i n e o f symmet ry , t h e f o r c e i s d i r e c t e d a t an i n c l i n a t i o n t o t h e normal t o t h e b o r e h o l e w a l l . T h i s means t h a t p r e s s u r e on t h e w a l l i s n o t u n i f o r m and t h e t h e o r e t i c a l s o l u t i o n f o r t h e d e f o r m a t i o n modulus i n v o l v e s a c o n s t a n t d i s p l a c e m e n t p r o b l e m r a t h e r t h a n c o n s t a n t p r e s s u r e . [Goodman, e t a l _ . 12] T r a n [ 7 ] s t a t e d t h e f o l l o w i n g a s s u m p t i o n s f o r t h e a n a l y t i c a l s o l u t i o n f o r t h e b o r e h o l e j a c k p r o b l e m : \" 1 . The m a t e r i a l s t u d i e d i s homogeneous, i s o t r o p i c and l i n e a r l y e l a s t i c and t h e b o r e h o l e i s p e r f e c t l y s m o o t h . 2 . The a p p l i e d p r e s s u r e i s u n i a x i a l and u n i f o r m a c r o s s t h e w i d t h o f t h e p l a t e , and a l o n g t h e a x i s o f t h e b o r e h o l e . I t a c t s a t t h e w a l l o f t h e b o r e h o l e . 3 . E x t e r n a l s h e a r l o a d does n o t e x i s t , i . e . , t h e j a c k i s f r i c t i o n l e s s . 4 . The j a c k i s i n f i n i t e l y l o n g i n t h e t h i r d d i m e n s i o n . \" U s i n g t h e c o m p l e x v a r i a b l e method t h e f o l l o w i n g s o l u t i o n was p r e s e n t e d f o r t h e d e f o r m a t i o n m o d u l u s : Qd E = K(v, 3) ^ . . . . ( 1 ) °d where E d e f o r m a t i o n modulus K c o n s t a n t w h i c h i s a f u n c t i o n o f P o i s s o n ' s r a t i o , v, and t h e p l a t e w i d t h , 6 Q p r e s s u r e a p p l i e d t o t h e r o c k d d i a m e t e r o f t h e b o r e h o l e U j a v e r a g e d i a m e t r a l d i s p l a c e m e n t . E q u a t i o n ( 1 ) , a l t h o u g h m a t h e m a t i c a l l y c o r r e c t , i s s u b j e c t t o t h e a s s u m p t i o n s s t a t e d above and hence i s n o t s t r i c t l y a p p l i c a b l e t o t h e f i e l d c o n d i t i o n s . Goodman e t a l _ . [ 1 2 ] i n v e s t i g a t e d t h e e f f e c t s 33 o f t h e a s s u m p t i o n s and o t h e r f a c t o r s on t h e m a t h e m a t i c a l s o l u t i o n and r e f i n e d e q u a t i o n (1) f o r t h e i n t e r p r e t a t i o n o f f i e l d t e s t d a t a . T h e i r f i n d i n g s w i l l b r i e f l y be s u m m a r i z e d : 1 . The c o n s t a n t , K ( v , 3 ) , i s a maximum a t 3 = 45 d e g r e e s , t h e p l a t e w i d t h o f t h e Goodman J a c k . 2 . S i n c e t h e a n a l y t i c a l s o l u t i o n assumes l i n e a r e l a s t i c b e h a v i o u r , r o c k e x h i b i t i n g n o n - l i n e a r i t y c a n be i n t e r p r e t e d q u a l i t a t i v e l y b u t n o t q u a n t i t a t i v e l y . 3 . F i n i t e e l e m e n t a n a l y s i s showed t h a t t h e c o u p l i n g e f f e c t o f t h e s t e e l p l a t e and r o c k s u r f a c e i s m i n i m a l and t h a t t h e b o r e h o l e j a c k i s c l o s e -l y a p p r o x i m a t e d by t h e c o n s t a n t d i s p l a c e m e n t boundary c o n d i t i o n . 4 . The e f f e c t o f l o a d i n g a f i n i t e l e n g t h was i n v e s t i g a t e d w i t h a t h r e e d i m e n s i o n a l f i n i t e e l e m e n t programme. The f i n d i n g s i n d i c a t e d t h a t t h e d e f o r m a t i o n modulus v a l u e s s h o u l d be d e c r e a s e d by 14% t o t a k e i n t o a c c o u n t t h e t h i r d d i m e n s i o n . The r e v i s e d e q u a t i o n f o r t h e i n t e r p r e t a t i o n o f f i e l d d a t a was p r e s e n t e d by T r a n [ 7 ] : Q h E = K f — . . . . ( 2 ) where e d e f o r m a t i o n modulus K.p a c o n s t a n t w h i c h i s a f u n c t i o n o f P o i s s o n ' s r a t i o h y d r a u l i c p r e s s u r e d i a m e t r a l d i s p l a c e m e n t . 5 . As F i g u r e 10 shows K^(v ) i s r e l a t i v e l y i n s e n s i t i v e t o v a r i a t i o n i n P o i s s o n ' s r a t i o . A s s u m p t i o n s f o r v t h u s i n t r o d u c e m i n i m a l Poisson's r a t i o e r r o r s t o t h e c a l c u l a t e d v a l u e o f d e f o r m a t i o n m o d u l u s . 6 . The p o s s i b i l i t y o f c r a c k f o r m a t i o n i n t h e p l a n e p e r p e n d i c -u l a r t o t h e j a c k l o a d i n g was a l s o i n v e s t i g a t e d w i t h a f i n i t e e l e m e n t m o d e l . T h i s s t u d y showed t h a t t h e p r o b a b l e maximum d e p t h o f c r a c k w o u l d be o n e - h a l f t o one r a d i u s beyond t h e h o l e . T h i s w o u l d r e s u l t i n an a p p a r e n t modulus 15% l e s s t h a n t h e t r u e v a l u e . S h o u l d t h e j a c k i n g t a k e p l a c e a c r o s s a p r e - e x i s t i n g c r a c k s u c h as a j o i n t t h e c o r r e c t i o n t o t h e d e f o r m a t i o n modulus c o u l d r e a c h 30%. 7 . The e f f e c t o f b o r e h o l e r o u g h n e s s i s n e g l i g i b l e a f t e r t h e f i r s t l o a d i n c r e m e n t s p r o v i d i n g c o m p l e t e u n l o a d i n g does n o t o c c u r . 8 . S t u d y o f t h e d i s p l a c e m e n t and p r e s s u r e d e c a y w i t h d e p t h f r o m t h e b o r e h o l e i n d i c a t e d t h e vo lume o f r o c k a f f e c t e d by t h e Goodman J a c k i s a p p r o x i m a t e l y one c u b i c f o o t . I t i s a p p a r e n t f r o m t h e f o r e g o i n g d i s c u s s i o n t h a t a s i g n i f i c a n t amount o f t h e o r e t i c a l f o r m u l a t i o n has gone i n t o t h e d e v e l o p m e n t o f t h e Goodman J a c k . V e r i f i c a t i o n o f t h e j a c k ' s b e h a v i o u r by c o m p a r i s o n o f f i e l d r e s u l t s w i t h o t h e r t e s t i n g t e c h n i q u e s i s t h e r e f o r e v a l u a b l e . C. P l a t e Load T e s t s In o r d e r t o i n t e r p r e t t h e r e s u l t s o f p l a t e l o a d i n g t e s t s , a s s u m p t i o n s must be made a b o u t t h e s t r e s s d i s t r i b u t i o n b e n e a t h t h e b e a r i n g p a d s . The u s u a l method assumes t h a t t h e r o c k behaves as a s e m i - i n f i n i t e e l a s t i c s o l i d u n d e r t h e a c t i o n o f a p o i n t normal l o a d . The s t a n d a r d B o u s s i n e s q s o l u t i o n i s t o o b t a i n e q u a t i o n s f o r t h e de fo rma p r e s e n t e d by Roark [ 1 3 ] , a r e as f o l f o r t h e c i r c u l a r p l a t e : E f o r t h e s q u a r e p l a t e : E t h e n a p p l i e d t o t h e p l a t e d e f l e c t i o n s ; i o n m o d u l u s . These e q u a t i o n s , as ows : P Q - v 2 ) ( 3 ) 2 r w . . . . 1 -9 p b ( l - v 2 ) . . . where E d e f o r m a t i o n modulus P c o n c e n t r a t e d normal l o a d v P o i s s o n ' s r a t i o r d i s t a n c e between p o i n t o f l o a d a p p l i c a t i o n and p o i n t o f d e f l e c t i o n ' m e a s u r e m e n t w d e f l e c t i o n p p r e s s u r e ( p s i ) b d i s t a n c e f r o m c e n t e r o f b e a r i n g p l a t e t o edge . The a s s u m p t i o n s i n t h e f o r m u l a t i o n o f e q u a t i o n s f o r modulus l e a d t o i n a c c u r a c i e s i n t h e i n t e r p r e t a t i o n o f p l a t e l o a d i n g t e s t r e s u l t s . The s o l u t i o n assumes an e l a s t i c and i s o t r o p i c medium, c o n d i t i o n s r a r e l y f o u n d i n r o c k . When t h e e q u a t i o n s a r e a p p l i e d t o p l a t e l o a d i n g t e s t s c a r r i e d o u t i n d r i f t s t h e d e p a r t u r e f r o m i d e a l i s even g r e a t e r . T h i s i s c a u s e d by t h e f a c t t h a t due t o t h e e x c a v a t i o n p r o c e s s a zone o f b l a s t damaged and d e s t r e s s e d r o c k s u r r o u n d s t h e d r i f t . The m i c r o -f r a c t u r i n g o f t h e r o c k i s most i n t e n s e a t t h e d r i f t w a l l s and d e c r e a s e s r a p i d l y w i t h d e p t h . T h i s means t h a t t h e a s s u m p t i o n s o f an e l a s t i c and i s o t r o p i c m a t e r i a l a r e i n c o n s i d e r a b l e e r r o r . Benson e t a l _ . [ 1 4 ] have 37 s t a t e d t h a t \" t h e g r e a t e s t s o u r c e s o f e r r o r w i t h t h e a s s u m p t i o n o f i s o t r o p y a r e t h a t e l a s t i c i t y p r e v a i l s and t h a t t h e modulus r e m a i n s c o n -s t a n t w i t h d e p t h . \" A f u r t h e r p r o b l e m w i t h p l a t e l o a d i n g t e s t s i s c a u s e d by t h e f a c t t h a t a l t h o u g h t h e a p p l i e d l o a d s a r e h i g h t h e i n d u c e d s t r e s s e s a r e l o w . F o r e x a m p l e , t h e 200 t o n l o a d s o f t h e t e s t s i n t h i s r e p o r t c o r r e s p o n d e d t o s t r e s s e s o f o n l y 4000 p s i . T h i s means t h a t f o r v e r y r i g i d r o c k t h e a c c u r a c y o f t h e d i a l gauges can be a s i g n i f i c a n t f r a c t i o n o f t h e d e f l e c t i o n c a u s e d by t h e j a c k i n g . T h i s c a n r e s u l t i n c o n s i d e r a b l e e r r o r i n t h e d e t e r m i n e d d e f o r m a t i o n modu lus v a l u e s . In l i g h t o f t h e f o r e g o i n g d i s c u s s i o n i t i s o b v i o u s t h a t p l a t e l o a d i n g t e s t s must be i n t e r p r e t e d w i t h a g r e a t d e a l o f c a u t i o n . D. D e f i n i t i o n o f Modulus Types A l t h o u g h t h e t e r m d e f o r m a t i o n modulus r e f e r s t o a s p e c i f i c r o c k p r o p e r t y , f u r t h e r d e f i n i t i o n i s r e q u i r e d i n o r d e r t o compare t h e r e s u l t s o f v a r i o u s t e s t i n g t e c h n i q u e s . The r e a s o n f o r t h i s i s t h a t s e v e r a l t y p e s o f d e f o r m a t i o n modu lus e x i s t d e p e n d i n g on t h e i r l o c a t i o n on t h e s t r e s s - s t r a i n c u r v e . F o r t h e p u r p o s e o f t h i s t h e s i s , t h r e e t y p e s o f d e f o r m a t i o n modulus w i l l be d e f i n e d . : The d e f i n i t i o n s c o r r e s p o n d t o t h o s e d e f i n e d by t h e company p e r f o r m i n g t h e p l a t e l o a d t e s t i n g i n o r d e r t h a t v a l i d c o m p a r i s o n s may be made between t e s t i n g m e t h o d s . A f u r t h e r c o n s i d e r a t i o n i n t h e modulus d e f i n i t i o n s was t h e d e s i r e t o have c o m p u t a t i o n s au tomated i n o r d e r t o u t i l i z e t h e c o m p u t e r . The company p e r f o r m i n g t h e p l a t e l o a d t e s t i n g d e f i n e d t h e f o l l o w i n g t h r e e d e f o r m a t i o n m o d u l i : 1 . W o r k i n g m o d u l u s , E w : \"A t a n g e n t modulus t a k e n a t a p o i n t on t h e s t r e s s - s t r a i n c u r v e w h i c h b e s t r e p r e s e n t s t h e b e h a v i o u r o f t h e m a t e r i a l . \" 2 . S e c a n t m o d u l u s , E g : \"The s e c a n t modu lus i s computed u s i n g maximum s t r e s s and s t r a i n v a l u e s . A s e c a n t modulus g r e a t l y l o w e r t h a n t h e w o r k i n g modulus u s u a l l y i n d i c a t e s open f r a c t u r e s i n t h e m a t e r i a l p e r m i t t i n g h i g h i n i t i a l s t r a i n o r a p l a s t i c m a t e r i a l t h a t c r e e p s under l o a d . \" 3 . R e c o v e r y m o d u l u s , E^: \"The r e c o v e r y modulus i s a s e c a n t modu lus t a k e n on t h e r e c o v e r y c u r v e . I t s v a l u e i n c r e a s e s as t h e e l a s t i c r e s p o n s e o f t h e m a t e r i a l d e c r e a s e s . \" These d e f i n i t i o n s a r e i l l u s t r a t e d i n F i g u r e 1 1 , w h i c h i s a t y p i c a l l o a d -d e f o r m a t i o n c u r v e f o r t h e p l a t e l o a d i n g t e s t s . In s p i t e o f t he f a c t t h a t t h e p l a t e l o a d i n g t e s t s u t i l i z e d i n c r e a s i n g c y c l i c l o a d s whereas t h e l a b o r a t o r y t e s t s and Goodman J a c k t e s t s c y c l e d t o a c o n s t a n t maximum l o a d , t h r e e s i m i l a r m o d u l i c a n be d e f i n e d f o r t h e l a t t e r two t e s t s . The d e f i n i t i o n s a r e i l l u s t r a t e d i n F i g u r e 1 2 . Note t h a t t h e p e r c e n t a g e e l a s t i c r e c o v e r y f o r t h e e n t i r e t e s t l o a d i n g i s e q u i v a l e n t t o t h e r a t i o o f t h e s e c a n t t o r e c o v e r y m o d u l u s . I t s h o u l d a l s o be n o t e d t h a t t h e w o r k i n g modulus f o r t h e s e t e s t s i s a c h o r d modulus r a t h e r t h a n a t a n g e n t m o d u l u s . T h e r e were two main r e a s o n s f o r t h i s . F i r s t l y , i t i s v e r y d i f f i c u l t t o programme t h e MODULUS DEFINITIONS FOR PLATE LOADING TESTS MODULUS DEFINITIONS FOR LABORATORY AND GOODMAN JACK TESTS E = chord modulus between p o i n t s 1 and 2 w Goodman Jack Tests: p o i n t 1 = 1/3 maximum s t r e s s -Laboratory T e s t s : p o i n t 1 = 1 / 2 maximum s t r e s s c o m p u t e r t o c a l c u l a t e a t a n g e n t modulus f r o m a s e t o f s t r e s s - s t r a i n r e a d i n g s . On t h e o t h e r h a n d , a c h o r d modulus c a l c u l a t i o n i s v e r y e a s i l y programmed. S e c o n d l y , i t was f e l t t h a t c o m p a r i s o n s o f w o r k i n g modulus between r o c k t y p e s w o u l d be more v a l i d i f t h i s modulus was r e l a t e d t o t h e shape o f t h e s t r e s s - s t r a i n c u r v e . In o t h e r w o r d s , t h e w o r k i n g modulus was d e t e r m i n e d o v e r t h e most l i n e a r p o r t i o n o f t h e s t r e s s - s t r a i n c u r v e r e g a r d l e s s o f s t r e s s l e v e l . In t h e a u t h o r ' s o p i n i o n t h i s c o m p a r i s o n i s more m e a n i n g f u l t h a n t h e u s u a l p r a c t i c e o f c o m p a r i n g t a n g e n t m o d u l i o f v a r i o u s r o c k t y p e s a t c o i n c i d e n t s t r e s s l e v e l s . T h i s l a t t e r p r a c t i c e i n t r o d u c e s t h e v a r i a t i o n o f l i n e a r i t y o f t h e s t r e s s -s t r a i n c u r v e s i n t o t h e c o m p a r i s o n ; an e f f e c t w h i c h can be q u i t e s i g n i f i -c a n t f o r r o c k t y p e s o f d i f f e r i n g . c o m p e t e n c y . 42 CHAPTER VI RESULTS OF TESTING PROGRAMMES The d e t a i l e d r e s u l t s o f e a c h t e s t i n g programme a r e p r e s e n t e d i n t h e a p p e n d i c e s . In t h i s s e c t i o n t h e r e s u l t s o f t h e v a r i o u s t e s t i n g t e c h n i q u e s a r e compared and a n a l y z e d i n a c c o r d w i t h d e f i n i t i o n s o u t l i n e d i n c h a p t e r V . D . A . L a b o r a t o r y T e s t i n g Programme S e v e n t y - o n e s a m p l e s were t e s t e d i n t h e l a b o r a t o r y t e s t i n g programme a l t h o u g h a l l s a m p l e s d i d n o t y i e l d u s u a b l e r e s u l t s . The t h r e e m o d u l i p r e v i o u s l y d e f i n e d were c a l c u l a t e d f o r e a c h c y c l e o f l o a d -i n g . The w o r k i n g m o d u l u s , b e c a u s e i t b e s t r e p r e s e n t s t h e r o c k b e h a v i o u r , was used as t h e b a s i s f o r c o m p a r i s o n . The s e c a n t and r e c o v e r y m o d u l i were used t o i n t e r p r e t t h e t y p e o f d e f o r m a t i o n s t a k i n g p l a c e . D u r i n g p r e l i m i n a r y s t u d i e s t h e w o r k i n g modulus was t a k e n o v e r t h e upper t w o -t h i r d s o f t h e s t r e s s - s t r a i n c u r v e . A n a l y s i s o f t h e s t r e s s - s t r a i n c u r v e s showed t h a t t h i s v a l u e i n c l u d e d s i g n i f i c a n t n o n - l i n e a r d e f o r m a t i o n . The w o r k i n g modulus was t h e n r e v i s e d t o i n c l u d e o n l y t h e upper o n e - h a l f o f t h e s t r e s s - s t r a i n c u r v e . P r i o r t o i n i t i a t i n g r o c k t e s t i n g an a luminum sample was t e s t e d t o c h e c k t h e i n s t r u m e n t a t i o n . F i g u r e 13 shows t h e s t r e s s - s t r a i n c u r v e f o r t h e a luminum s a m p l e . As c a n be s e e n t h e c u r v e i n d i c a t e s a p e r f e c t Sample No. Aluminum LABORATORY TESTING AXIAL STRESS vs. AXIAL STRAIN Rock Type First cycle Second cycle 20,000 16.000 12,000 8,000 4,000 Strain ( x 10 ) 44 l i n e a r l y e l a s t i c m a t e r i a l . T h i s c o n f i r m s t h a t t h e l o a d c e l l and r e a d o u t u n i t were c a l i b r a t e d c o r r e c t l y . The s e c a n t , w o r k i n g and r e c o v e r y m o d u l i a l l have v a l u e s o f 1 0 . 4 x 1 0 6 p s i f o r b o t h l o a d i n g c y c l e s . P o i s s o n ' s r a t i o f o r t h i s sample i s 0 . 3 5 . The p u b l i s h e d v a l u e s f o r modulus o f e l a s t i c i t y and P o i s s o n ' s r a t i o f o r pu re a luminum and a l l o y s a r e 9 . 9 - 1 1 . 4 x 1 0 6 p s i and 0 . 3 2 - 0 . 3 4 r e s p e c t i v e l y . [ S m i t h e l l s , 15] These r e s u l t s i n d i c a t e d t h a t t h e s t r a i n gauge s y s t e m and l o a d s e n s i n g s y s t e m o p e r a t e d c o r r e c t l y and p r o v i d e d a means o f c h e c k i n g t h e s t a t e o f t h e t e s t i n g s y s t e m i n t h e c o u r s e o f t h e e x p e r i m e n t a l w o r k . 1 . Q u a r t z i t e G n e i s s F o r t y - t w o q u a r t z i t e g n e i s s s a m p l e s were t e s t e d o f w h i c h 39 y i e l d e d u s a b l e r e s u l t s . As s t a t e d e a r l i e r t h i s r o c k t y p e t e n d s t o be u n i f o r m , homogeneous and l a c k i n g f o l i a t i o n . A s m a l l number o f s a m p l e s d i d e x h i b i t n o n - u n i f o r m i t y as e i t h e r f a i n t f o l i a t i o n , c h l o r i t i z a t i o n bands o r h e a l e d f r a c t u r e s . The g n e i s s s a m p l e s were f i t t e d w i t h two a x i a l and two c i r c u m -f e r e n t i a l s t r a i n g a u g e s . T h i s a l l o w e d c a l c u l a t i o n o f P o i s s o n ' s r a t i o as w e l l as t h e v a r i o u s d e f o r m a t i o n m o d u l i . The P o i s s o n ' s r a t i o v a l u e s were d e t e r m i n e d o n l y t o c h e c k t h o s e v a l u e s assumed f o r t h e Goodman J a c k t e s t i n g and t h u s t h e v a l u e s w i l l be r e p o r t e d w i t h l i t t l e d i s c u s s i o n . F o r t h e g n e i s s e s , P o i s s o n ' s r a t i o g e n e r a l l y i n c r e a s e d f r o m 0 . 0 5 t o 0 . 3 5 ( a p p r o x i m a t e l y ) as t h e l o a d i n c r e a s e d . A l t h o u g h q u i t e v a r i a b l e , t h e a v e r a g e v a l u e was a b o u t 0 . 2 0 . Some v a l u e s g r e a t e r t h a n t h e t h e o r e t i c a l 0 . 5 . maximum were r e c o r d e d , r e i n f o r c i n g Hawkes ' [ 1 6 ] c l a i m t h a t f o r r o c k P o i s s o n ' s r a t i o i s m e a n i n g l e s s . S e v e r a l r e a s o n s f o r 45 i n c o n s i s t e n t P o i s s o n ' s r a t i o v a l u e s f o r r o c k have been r e p o r t e d . A t l o w s t r e s s l e v e l s p o r e and m i c r o f r a c t u r e c l o s u r e a c c o u n t s f o r most o f t h e a x i a l s t r a i n . T h i s i n e l a s t i c d e f o r m a t i o n p r o d u c e s l i t t l e l a t e r a l s t r a i n hence t h e l o w P o i s s o n ' s r a t i o v a l u e s . [Hawkes , 16 ] A n o t h e r f a c t o r t h a t can i n f l u e n c e P o i s s o n ' s r a t i o i s t h e p o s i t i o n i n g o f t h e s t r a i n gauges r e l a t i v e t o g e o l o g i c f e a t u r e s s u c h as f o l i a t i o n o r r e l a t i v e t o l o c a l s t r e s s c o n c e n t r a t i o n s w i t h i n t h e s a m p l e . F i g u r e s 1 4 , 1 5 , and 16 i l l u s t r a t e s t r e s s v e r s u s s t r a i n c u r v e s f o r l a b o r a t o r y t e s t s on t h e q u a r t z i t e g n e i s s s a m p l e s . These c u r v e s a r e t y p i c a l o f t h o s e f o r t h i s r o c k t y p e and a r e r e p r e s e n t a t i v e o f t h e g n e i s s b e h a v i o u r . These f i g u r e s i l l u s t r a t e s e v e r a l d e f o r m a t i o n c h a r a c t e r i s t i c s o f t h e g n e i s s . The most s t r i k i n g f e a t u r e i s t h e s m a l l amount o f i n -e l a s t i c d e f o r m a t i o n . F o r t h e g r a p h s shown t h e r e s i d u a l i n e l a s t i c d e f o r m a t i o n amounted t o an a v e r a g e o f o n l y 9% o f t h e t o t a l d e f o r m a t i o n . S i n c e t h e u n l o a d i n g c u r v e s f o r b o t h c y c l e s a r e v e r y n e a r l y c o i n c i d e n t , n e g l i g i b l e i n e l a s t i c d e f o r m a t i o n o c c u r s a f t e r t h e f i r s t c y c l e . S e c o n d l y , t h e n a r r o w w i d t h o f t h e l o a d - u n l o a d l o o p s i n d i c a t e s s m a l l h y s t e r e s i s e f f e c t s . A t h i r d f e a t u r e o f t h e s e c u r v e s i s t h a t a f t e r t h e i n i t i a l c u r v i l i n e a r p o r t i o n t h e c u r v e s become l i n e a r . T h i s i s a d e s i r a b l e r o c k p r o p e r t y b e c a u s e i t a l l o w s a c c u r a t e p r e d i c t i o n o f r o c k b e h a v i o u r u n d e r l o a d . T h i s l i n e a r i t y a l s o means t h a t t h e w o r k i n g modulus c a l c u l a t e d f o r t h e u p p e r 50% o f t h e l o a d i n g c u r v e v e r y n e a r l y a p p r o a c h e s a t a n g e n t modulus f o r t h i s c u r v e . In o r d e r t o r e d u c e t h e d a t a t o a form, more e a s i l y a n a l y z e d , d i s t r i b u t i o n d i a g r a m s were p r e p a r e d f o r f i r s t and s e c o n d c y c l e Sample No. 20,000 16,000 12,000 8,000 4,000 N6 LABORATORY TESTING AXIAL STRESS vs. AXIAL STRAIN First cycle Rock Type q u a r t z i t e gneiss Second cycle -- f * ///' X''/'' yi ** -f 4 f + A y * jKr / * A* f s f**- • • — * --1 1 1 1 i 1 -3 Strain ( X 10 ) -s CO Sample No. 20,000 N23 LABORATORY TESTING AXIAL STRESS vs. AXIAL STRAIN First cycle Second cycle Rock Type q u a r t z i t e gneiss 16,000 Sample No. N93 20,000 16,000 12,000 8,000 4,000 LABORATORY TESTING AXIAL STRESS vs. AXIAL STRAIN F irst cycle Second cycle Rock Type guartzite gneiss Strain ( x 10 ) i n c -s CT1 00 49 d e f o r m a t i o n m o d u l i . F i g u r e 17 shows d i s t r i b u t i o n d i a g r a m s f o r f i r s t and s e c o n d c y c l e w o r k i n g modulus f o r t h o s e g n e i s s samp les where b o t h l o a d i n g c y c l e s were c o m p l e t e d . The s i g n i f i c a n t f e a t u r e s o f t h e s e d i s t r i -b u t i o n d i a g r a m s a r e as f o l l o w : 1 . The mean and s t a n d a r d d e v i a t i o n o f t h e f i r s t c y c l e w o r k i n g fi ft modulus a r e 7 . 8 6 x 10 p s i and 1 .04 x 10 p s i r e s p e c t i v e l y . The s t a n d a r d d e v i a t i o n e x p r e s s e d as a p e r c e n t o f t h e mean, known as t h e c o e f f i c i e n t o f v a r i a t i o n , i s 13%. 2 . The mean and s t a n d a r d d e v i a t i o n o f t h e s e c o n d c y c l e w o r k i n g modu lus a r e 8.41 x 1 0 6 p s i and 0 . 9 4 x 1 0 6 p s i r e s p e c t i v e l y . The c o e f f i c i e n t o f v a r i a t i o n i s 11%. 3 . A l t h o u g h t h e d i s t r i b u t i o n s a r e s l i g h t l y s k e w e d , t h e r e i s s u g g e s t i o n t h a t b o t h f i r s t and s e c o n d c y c l e d i s t r i b u t i o n s a r e a p p r o a c h i n g t h e normal d i s t r i b u t i o n . T h i s i s a q u e s t i o n -a b l e s t a t e m e n t due t o t h e s m a l l number o f t e s t r e s u l t s . The f a c t t h a t t h e s e c o n d c y c l e mean w o r k i n g modu lus i s 7% g r e a t e r t h a n t h a t o f t h e f i r s t c y c l e must be r e l a t e d t o t h e f a c t t h a t v e r y l i t t l e i n e l a s t i c d e f o r m a t i o n i s o c c u r r i n g on t h e s e c o n d c y c l e . T h a t i s , t h e c l o s u r e o f m i c r o f r a c t u r e s and p o r o s i t y t a k e s p l a c e d u r i n g t h e f i r s t l o a d i n g c y c l e r e s u l t i n g i n a l o w e r m o d u l u s . By l i s t i n g t h e s e c o n d c y c l e w o r k i n g m o d u l i a l o n g w i t h t h e c o r r e s p o n d i n g sample d e s c r i p t i o n s no r e l a t i o n s h i p i s o b v i o u s between modu lus and any o f t h e f o l l o w i n g : g r a i n s i z e , f o l i a t i o n , o r c h l o r i t i z a t i o n . T h i s f a c t s u p p o r t s t h e h y p o t h e s i s t h a t t h e modulus v a l u e s s h o u l d be n o r m a l l y d i s t r i b u t e d . Frequency F i r s t Cycle Working Modulus F i g u r e 15 mode = mean = 7.86 x 10 10 36 values J I I L 8.50.x 10 0 1 2 3 4 5 6 7 8 9 10 11 12 Frequency Modulus ( p s i x 10 ) Second Cycle Working Modulus 15 mode = 7.50 x 10 •6 10 36 values 5 h mean = 8.41 x 10 0 1 2 3 4 5 6 7 8 9 10 11 12 Modulus ( p s i x 10 ) FREQUENCY HISTOGRAMS FOR .LABORATORY TESTS OF QUARTZITE GNEISS 51 A l t h o u g h v e r y few g n e i s s s a m p l e s e x h i b i t e d f o l i a t i o n , t h e a n i s o t r o p y o f t h i s r o c k t y p e c a n be i n v e s t i g a t e d by p l o t t i n g modu lus v e r s u s f o l i a t i o n a n g l e . The f o l i a t i o n a n g l e f o r t h i s r e p o r t i s d e f i n e d as t h e a c u t e a n g l e between t h e a x i s o f t h e samp le ( i . e . l o a d i n g d i r e c t i o n ) and t h e p l a n e o f t h e f o l i a t i o n . F i g u r e 18 shows t h e p l o t s o f f i r s t and s e c o n d c y c l e w o r k i n g modulus v e r s u s f o l i a t i o n a n g l e . From t h e l i m i t e d d a t a a v a i l a b l e t h e r e l a t i o n s h i p between w o r k i n g modulus and o r i e n t a t i o n o f m i c a p a r t i c l e s i s u n c e r t a i n . An i m p o r t a n t p r o p e r t y o f r o c k , f r o m a d e s i g n v i e w p o i n t , i s i t s a b i l i t y t o undergo permanent d e f o r m a t i o n upon l o a d i n g . T h i s i n e l a s t i c b e h a v i o u r becomes i m p o r t a n t i n r o c k s t r u c t u r e s s u b j e c t t o c y c l i c l o a d i n g . The i n e l a s t i c i t y o f t h e r o c k s a m p l e s t e s t e d i n t h e l a b o r a t o r y was q u a n t i t a t i v e l y s t u d i e d u s i n g two p a r a m e t e r s : 1 . The p e r c e n t a g e e l a s t i c r e c o v e r y f o r t h e c o m p l e t e t e s t l o a d i n g and f o r t h e s e c o n d c y c l e o f l o a d i n g . 2 . The r a t i o o f t h e w o r k i n g modu lus t o t h e s e c a n t m o d u l u s . The q u a r t z i t e g n e i s s s a m p l e s had an a v e r a g e 93% e l a s t i c r e c o v e r y f o r t h e e n t i r e t e s t l o a d i n g . T h i s v a l u e r a n g e d f r o m 84% t o 96% i n d i c a t -i n g t h a t t h e g n e i s s samp les undergo s m a l l amounts o f permanent d e f o r m a t i o n . The e l a s t i c r e c o v e r y f o r t h e s e c o n d c y c l e o f l o a d i n g r a n g e d f r o m 98% t o 99.8% w i t h an a v e r a g e o f 9 9 . 3 % . T h i s c o n c l u s i v e l y shows t h a t t h e g n e i s s i s a l m o s t p e r f e c t l y e l a s t i c a f t e r t h e f i r s t l o a d i n g c y c l e . 10.0 9.0 F i r s t Cycle Working 8.0 Modulus , ( p s i x 10 ) 7.0 6.0 5.0 4.0 10.0 9.0 Second Cycle Working Modulus , ' u ( p s i x 10 ) 7.0 6.0 52 ANISOTROPY DIAGRAMS FOR QUARTZITE GNEISS ( L a b o r a t o r y T e s t i n g ) F i 9 u r e 1 8 • • • • • 0 10 20 30 40 50 60 70 80 90 F o l i a t i o n Angle (degrees) > • • » • 5.0 0 10 20 30 40 50 60 70 80 90 F o l i a t i o n Angle (degrees) 53 As p r e v i o u s l y s t a t e d a w o r k i n g modulus s i g n i f i c a n t l y g r e a t e r t h a n t h e s e c a n t modulus i s an i n d i c a t i o n o f open f r a c t u r e s i n a r o c k s a m p l e . A r a t i o o f E w t o E g s i g n i f i c a n t l y g r e a t e r t h a n 1 . 0 w o u l d i n d i c a t e l i k e w i s e . F o r t h e g n e i s s s a m p l e s , t h e r a t i o , E w / E s r a n g e d f r o m 1 .09 t o 1 .47 and a v e r a g e d 1 . 2 2 . T h i s i n d i c a t e s t h e l a b o r a t o r y s a m p l e s a r e r e l a t i v e l y f r e e o f open f r a c t u r e s t h e r e b y r e i n f o r c i n g t h e above c o n c l u s i o n t h a t t h e g n e i s s s a m p l e s have e l a s t i c d e f o r m a t i o n c h a r a c t e r i s t i c s . 2 . Q u a r t z F e l d s p a r S c h i s t T w e n t y - t h r e e q u a r t z f e l d s p a r s c h i s t s a m p l e s were t e s t e d a l l o f w h i c h y i e l d e d u s a b l e r e s u l t s . T h i s r o c k t y p e e x h i b i t s d i s t i n c t f o l i a t i o n so t h a t a l l modulus v a l u e s must be r e l a t e d t o t h i s f e a t u r e . The s c h i s t samp les were f i t t e d w i t h f o u r a x i a l s t r a i n g a u g e s . These gauges were l o c a t e d w i t h r e s p e c t t o t h e f o l i a t i o n ( F i g u r e 5) so t h a t one s e t was l o c a t e d p a r a l l e l t o t h e s t r i k e d i r e c t i o n w h i l e t h e s e c o n d s e t was l o c a t e d p a r a l l e l t o t h e d i p d i r e c t i o n . By m o n i t o r i n g t h e s e s e t s o f gauges on i n d i v i d u a l s t r a i n b o x e s , r e s u l t s were o b t a i n e d w h i c h w o u l d i l l u s t r a t e t h e d e f o r m a t i o n c h a r a c t e r i s t i c s i n t h e s e two d i r e c t i o n s . F i g u r e s 19 t h r o u g h 24 i l l u s t r a t e s t r e s s - s t r a i n c u r v e s f o r t h e s t r i k e and d i p d i r e c t i o n o f t h r e e s a m p l e s . These f i g u r e s show t h e r a n g e o f d e f o r m a t i o n b e h a v i o u r e x h i b i t e d by t h e s c h i s t s a m p l e s . F i g u r e s 19 and 20 show t h e b e h a v i o u r o f s a m p l e s w i t h a h i g h f o l i a t i o n a n g l e (70 t o 90 d e g r e e s ) . These s a m p l e s a r e c h a r a c t e r i z e d by l a r g e d e f o r m a t i o n s , Sample No, Foliation Angle N40 s t r i k e 70 LABORATORY TESTING AXIAL STRESS vs. AXIAL STRAIN Rock Type quartz-feldspa r schist F i rst cycle Second cycle t/1 o O) 4,000 3,200 2,400 1 ,600 800 0.0 IX) c_n Strain ( X 10 ) Sample No, N40 d i p o Foliation Angle 70 LABORATORY TESTING AXIAL STRESS vs. AXIAL STRAIN Rock guartz-feldspa Type schist F i rst cycle . _. Second cycle 4,000 | 1 1 1 1 1 1 Sample No, N70 strike Foliation Angle 0° LABORATORY TESTING AXIAL STRESS vs. AXIAL STRAIN Rock quartz-feldspar-Type schist F i rst cycle Second cycle 4,000 3,200 4 5 6 7 8 9 10 11 12 Modulus ( p s i x 10 ) F r e q u e n c y 15 10 Second C y c l e W o r k i n g Modu lus mode = 3 . 5 0 x 10 22 v a l u e s mean = 4.3.2 x 10 0 1 2 3 4 5 6 7 8 9 10 11 12 Modu lus ( p s i x 1 0 6 ) FREQUENCY HISTOGRAMS FOR LABORATORY TESTS OF QUARTZ FELDSPAR SCHIST 62 s t a n d a r d d e v i a t i o n = 2 . 5 8 x 10° p s i c o e f f i c i e n t o f v a r i a t i o n = 60% 3 . The modu lus v a l u e s have a w i d e r a n g e . The l a r g e s t a n d a r d d e v i a t i o n s and w i d e r a n g e o f modu lus v a l u e s r e f l e c t t h e dependence o f t h e modulus upon t h e f o l i a t i o n a n g l e . The a n i s o t r o p y o f t h e q u a r t z f e l d s p a r s c h i s t s a m p l e s i s c l e a r l y i l l u s t r a t e d i n F i g u r e 26 . Note t h a t t h i s d i a g r a m assumes t h a t t h e s c h i s t i s t r a n s v e r s l y i s o t r o p i c , i n o t h e r w o r d s , t h e modulus i s c o n s t a n t w i t h i n t h e p l a n e o f t h e f o l i a t i o n . The v e r y h i g h v a l u e s o f modu lus f o r l o w f o l i a t i o n a n g l e s c a n be e x p l a i n e d as f o l l o w s . I f t h e q u a r t z and f e l d s p a r l a y e r s w i t h i n t h e s c h i s t a r e assumed t o be c o n t i n u o u s , l o a d i n g p a r a l l e l t o t h e s e l a y e r s w o u l d r e s u l t i n a d i s p r o p o r t i o n a t e l y h i g h p e r c e n t a g e o f t h e l o a d b e i n g c a r r i e d by t h e s e l a y e r s . Thus t h e q u a r t z and f e l d s p a r l a y e r s a r e a c t i n g as h i g h modu lus i n c l u s i o n s c a u s i n g l o w d e f o r m a t i o n s and h i g h modu lus v a l u e s . The l o w modu lus v a l u e s o f i n t e r m e d i a t e f o l i a t i o n a n g l e s a r e most e a s i l y e x p l a i n e d by t h e f a c t t h a t a t t h e s e a n g l e s t h e f o l i a t i o n i s f a v o u r a b l y o r i e n t e d f o r i n t e r -l a y e r s l i p p a g e . T h i s w o u l d r e s u l t i n h i g h s t r a i n s and l o w modu lus v a l u e s . The s l i g h t i n c r e a s e i n modulus v a l u e s f o r h i g h f o l i a t i o n a n g l e s i s p r o b a b l y due t o t h e f a c t t h a t l i t t l e i n t e r - l a y e r movement o c c u r s and d e f o r m a t i o n i s due m a i n l y t o t h e c o m p r e s s i o n o f m i c a c e o u s l a y e r s . The d e f o r m a t i o n c h a r a c t e r i s t i c s o f t h e s c h i s t samp les as m o n i t o r e d i n t h e s t r i k e and d i p d i r e c t i o n s a r e i l l u s t r a t e d by F i g u r e 2 7 . ANISOTROPY DIAGRAM FOR QUARTZ FELDSPAR SCHIST L a b o r a t o r y T e s t i n g d e f o r m a t i o n o f c o m p e t e n t l a y e r s i n t e r - l a y e r movement c o m p r e s s i o n o f m i c a c e o u s l a y e r s Second C y c l e W o r k i n g Modulus ( p s i x 1 0 6 ) 1 2 . 0 1 0 . 0 8 . 0 6 . 0 4 . 0 2 . 0 \\ • \\ \\ • \\ -> • • \\ > \\ < -i \\ • < » ' - • — \" • \" F o l i a t i o n A n g l e ( d e g r e e s ) R A T I ° 0 F E w s t r i k e / E w d i p v s - FOLIATION ANGLE w s t r i k e E w d i P 1 . 5 1 .3 1.1 0 . 9 0 . 7 0 . 5 0 . 3 0 TO 20 30 40 50 60 70 80 90 F o l i a t i o n A n g l e to d -s CD ro 65 T h i s f i g u r e shows a p l o t o f t h e r a t i o E . ., / E ,. v e r s u s f o l i a t i o n 3 r w s t r i k e w d i p a n g l e . The g r a p h shows t h a t a t h i g h f o l i a t i o n a n g l e s t h e r a t i o a p p r o a c h e s u n i t y w i t h l i t t l e s c a t t e r . T h i s i s t o be e x p e c t e d s i n c e , a t a f o l i a t i o n a n g l e o f 90 d e g r e e s s t r i k e and d i p d i r e c t i o n s a r e i n d i s t i n g -u i s h a b l e and t h e r a t i o s h o u l d t h u s be u n i t y . F o r l o w f o l i a t i o n a n g l e s t h e r a t i o , E w s ^ - j k g / E > ~n to - 1 1 > I ( • 4 1 1 • » ( 1 ( • 10 20 30 40 50 60 70 80 90 ro ro F o l i a t i o n A n g l e 1 X 3 cr> . CO Sample No. N31 LABORATORY TESTING AXIAL STRESS vs. AXIAL STRAIN Rock Type p e g m a t i t e 20,000 16,000 12,000 8,000 4,000 F irst cycle Second cycle -5 ro C O o cn Sample No. N33 LABORATORY TESTING AXIAL STRESS vs. AXIAL STRAII Rock Type p e g m a t i t e Ul CL LO ul 0) i-CO c QJ E •r-U a> o. OO 20,000 16,000 12,000 8,000 4,000 F irst cycle Second cycle L Q C OJ TT6 O \" Strain ( X 10 3 ) 7 T \"372 o 71 4 . Summary and C o m p a r i s o n o f L a b o r a t o r y R e s u l t s The r e l a t i o n s h i p between s e c o n d c y c l e w o r k i n g modulus and u n i t w e i g h t f o r t h e l a b o r a t o r y samp les i s shown i n F i g u r e 3 2 . Two c o n c l u s i o n s can be drawn f rom t h i s g r a p h . F i r s t l y , t h e t h r e e r o c k t y p e s a r e r e a d i l y c l a s s i f i e d on t h e b a s i s o f modu lus and u n i t w e i g h t . S e c o n d l y , t h e w o r k i n g modulus and u n i t w e i g h t have an a p p r o x i m a t e i n v e r s e r e l a t i o n s h i p . T h i s i s due t o t h e f a c t t h a t t h e more d e f o r m a b l e m i c a c e o u s m i n e r a l s a r e a l s o t h e h e a v i e s t . The r e s u l t s o f t h e l a b o r a t o r y t e s t i n g programme a r e summar i zed i n T a b l e 2 f o r e a s y c o m p a r i s o n o f r o c k t y p e s . R e f e r r i n g t o T a b l e 2 i t i s n o t e d t h a t t h e a v e r a g e s e c o n d c y c l e w o r k i n g modulus f o r t h e q u a r t z i t e g n e i s s i s 1 .9 t i m e s t h a t o f t h e q u a r t z f e l d s p a r s c h i s t and 1 . 3 t i m e s t h a t o f t h e p e g m a t i t e . As i n d i c a t e d by t h e s t a n d a r d d e v i a t i o n and r a n g e o f w o r k i n g modulus v a l u e s , t h e s c h i s t samp les e x h i b i t e d f a r g r e a t e r v a r i a b i l i t y . As p r e v i o u s l y shown , t h i s v a r i a t i o n i s due t o t h e f o l i a t i o n . C o m p a r i s o n o f t h e s t r e s s - s t r a i n c u r v e s f o r t h e t h r e e r o c k t y p e s shows t h a t t h e g n e i s s and low f o l i a t i o n a n g l e s c h i s t samp les have l i n e a r s t r e s s - s t r a i n c u r v e s . The h i g h f o l i a t i o n a n g l e s c h i s t and p e g m a t i t e samp les t e n d t o have n o n - l i n e a r c u r v e s . A l l r o c k t y p e s e x c e p t h i g h a n g l e s c h i s t s e x h i b i t n e g l i g i b l e h y s t e r e s i s e f f e c t s . T h i s c o n d i t i o n i n h i g h a n g l e s c h i s t p r o b a b l y r e f l e c t s f r i c t i o n a l l o s s e s i n t h e c o m p r e s s i o n o f t h e m i c a c e o u s l a y e r s . The a v e r a g e e l a s t i c r e c o v e r y f o r a l l r o c k t y p e s i s s u i t a b l y h i g h f o r e n g i n e e r i n g p u r p o s e s ; 85% b e i n g c o n s i d e r e d s a t i s f a c t o r y . However , t h e s c h i s t s a m p l e s a r e q u i t e v a r i a b l e , r a n g i n g f r o m 75 t o 90% VARIATION OF MODULUS WITH UNIT WEIGHT FOR VARIOUS ROCK TYPES ( L a b o r a t o r y T e s t i n g ) • = q u a r t z i t e g n e i s s , ' + = q u a r t z f e l d s p a r s c h i s t , # = p e g m a t i t e 12 10 Second C y c l e W o r k i n g Modulus ( p s i x 1 0 6 ) -• + - ••• • • • 4 * + + + • •• • ^ •* . • * • + + + -+ + + i i i i 1 1 1 1 + + 1 1 1 1 l 1 1 1 1 1 1 I T60 165 170 175 180 185 U n i t W e i g h t ( l b / f r ) 73 TABLE 2 SUMMARY OF LABORATORY RESULTS N o t e : A l l modulus v a l u e s i n p s i x 1 0 6 P r o p e r t y Q u a r t z i t e G n e i s s Q u a r t z F e l d s p a r S c h i s t P e g m a t i t e a . Number o f samp les 42 23 6 b. Mean s e c o n d c y c l e s e c a n t modulus 6 . 4 0 3 . 0 6 3 . 8 6 c . Mean s e c o n d c y c l e r e c o v e r y modulus 6 . 8 8 3 . 6 8 4 . 3 2 d . Mean f i r s t c y c l e w o r k i n g modu lus 7 . 8 6 3 . 6 4 • 5 . 4 0 e . S t a n d a r d d e v i a t i o n o f d 1 .04 2 . 1 2 1 . 0 8 f . C o e f f i c i e n t o f v a r i a t i o n 13% 58% 20% •g. Mean s e c o n d c y c l e w o r k i n g modulus 8 .41 4 . 3 2 6 . 2 7 h. S t a n d a r d d e v i a t i o n o f g 0 . 9 4 2.61 1 .13 i . C o e f f i c i e n t o f v a r i a t i o n . 11% 60% 18% j . k. Range o f s e c o n d c y c l e w o r k i n g modulus % E , s e c o n d c y c l e g r e a t e r E f i r s t w 3 w 6 . 2 6 t o 10.1 1 .32 t o 1 0 . 7 4 . 6 4 t o 7 . 5 5 c y c l e 7% 19% 16% 1 . A v e r a g e % e l a s t i c r e c o v e r y f o r t o t a l t e s t 93% 84% 89% m. A v e r a g e % e l a s t i c r e c o v e r y f o r s e c o n d c y c l e 99% 99% 99% n . A v e r a g e r a t i o , E / E 3 w' s 1 .22 1 . 7 8 1 .66 The g n e i s s s a m p l e s a r e t h e most e l a s t i c f o l l o w e d by t h e p e g m a t i t e and t h e s c h i s t s a m p l e s . T h i s i n d i c a t e s t h a t t h e i n e l a s t i c d e f o r m a t i o n s may be r e l a t e d t o m i c a c o n t e n t . C o m p a r i s o n o f p r o p e r t i e s numbered k and n i n T a b l e 2 shows a c o r r e l a t i o n between t h e p e r c e n t a g e i n c r e a s e o f t h e s e c o n d c y c l e w o r k i n g modulus o v e r t h e f i r s t c y c l e and t h e a v e r a g e r a t i o , E / E . These w s r e s u l t s i n d i c a t e t h a t t h e g n e i s s s a m p l e s a r e r e l a t i v e l y f r e e o f m i c r o -f r a c t u r i n g compared t o t h e s c h i s t and p e g m a t i t e s a m p l e s . T h i s i s r e a s o n a b l e f o r t h e w e l l f o l i a t e d s c h i s t s a m p l e s b u t i s h a r d t o e x p l a i n f o r t h e p e g m a t i t e . A p o s s i b l e e x p l a n a t i o n i s t h a t t h e l a r g e g r a i n s o f t h e p e g m a t i t e a r e n o t w e l l c o n n e c t e d t h e r e b y a l l o w i n g i n t e r - g r a n u l a r movement under l o a d . B. Goodman J a c k T e s t i n g D u r i n g t h e c o u r s e o f t h e j a c k t e s t i n g 129. t e s t were p e r f o r m e d . . Many o f t h e s e i n d i v i d u a l t e s t s c o n s i s t e d o f 3 o r 4 l o a d i n g c y c l e s . G r e a t c a r e was t a k e n t o d i v i d e t h e s e t e s t s by r o c k t y p e . T h i s was done by c o m p a r i n g t h e t e s t d e p t h w i t h t h e b o r e h o l e l o g s . Any t e s t t h a t was c a r r i e d o u t w i t h i n one f o o t o f a r o c k t y p e boundary was r e j e c t e d and n o t i n c l u d e d i n t h e r e s u l t s o f t h i s t h e s i s . As f o r t h e l a b o r a t o r y t e s t i n g , t h e r o c k t y p e s c o n s i d e r e d were q u a r t z i t e g n e i s s , q u a r t z f e l d s p a r s c h i s t and p e g m a t i t e . In t h e c a s e o f t h e j a c k i n g t e s t s t h e w o r k i n g modulus was d e t e r m i n e d o v e r t h e u p p e r 2 / 3 o f t h e s t r e s s - d e f o r m a t i o n c u r v e . G e n e r a l l y , t h i s p o r t i o n o f t h e c u r v e was l i n e a r and e x p r e s s e d t h e b e h a v i o u r o f t h e r o c k . 75 I t i s a g a i n p o i n t e d o u t t h a t t h e Goodman J a c k t e s t s y i e l d e d s t r e s s - d e f o r m a t i o n c u r v e s r a t h e r t h a n s t r e s s - s t r a i n c u r v e s . The r e a s o n f o r t h i s i s t h a t no d e f o r m a t i o n r e a d i n g s c o u l d be t a k e n f o r t h e f i r s t l o a d i n c r e m e n t . As a r e s u l t t h e p e r c e n t e l a s t i c r e c o v e r y i s an a p p r o x i -m a t i o n c a l c u l a t e d f r o m t h e r e s i d u a l d e f o r m a t i o n a t 1000 p s i h y d r a u l i c p r e s s u r e . A l s o , t h e r a t i o o f w o r k i n g modulus t o s e c a n t m o d u l u s , an i n d i c a t i o n o f open f r a c t u r e s w i t h i n t h e r o c k o r b o r e h o l e w a l l r o u g h -n e s s , i s l e s s v a l u a b l e . The r e a s o n b e i n g t h a t a l a r g e p o r t i o n o f t h e i n e l a s t i c d e f o r m a t i o n w i l l o c c u r i n t h e f i r s t l o a d i n c r e m e n t and w i l l n o t be r e f l e c t e d by t h e s e c a n t m o d u l u s . As s t a t e d i n t h e s e c t i o n d e a l i n g w i t h t h e i n t e r p r e t a t i o n o f t h e t e s t d a t a , a c o n s t a n t d e p e n d e n t upon P o i s s o n ' s r a t i o i s n e c e s s a r y t o c a l c u l a t e modulus v a l u e s . The f o l l o w i n g v a l u e s f o r P o i s s o n ' s r a t i o were t h u s assumed : q u a r t z i t e g n e i s s : 0 . 2 0 q u a r t z f e l d s p a r s c h i s t : 0 . 3 5 p e g m a t i t e : 0 . 2 0 In o r d e r t o i n v e s t i g a t e t h e a n i s o t r o p y o f t h e r o c k mass i t i s n e c e s s a r y t o know t h e o r i e n t a t i o n o f t h e j a c k l o a d i n g w i t h r e s p e c t t o t h e f o l i a t i o n p l a n e s , w h i c h , as p r e v i o u s l y d e f i n e d , i s t h e f o l i a t i o n a n g l e . In o t h e r w o r d s , i t i s n e c e s s a r y t o know t h e o r i e n -t a t i o n o f t h e bo re h o l e and t h e a t t i t u d e o f t h e r o c k f o l i a t i o n a t t h e e x a c t p o s i t i o n s where t h e t e s t s a r e p e r f o r m e d . I d e a l l y , o r i e n t e d c o r e o r a b o r e h o l e camera t e c h n i q u e w o u l d p r o v i d e t h i s i n f o r m a t i o n . S i n c e n e i t h e r o f t h e s e t e c h n i q u e s were a v a i l a b l e an a l t e r n a t i v e method was u t i l i z e d . 76 The n e c e s s a r y d a t a f o r t h e method c o n s i s t e d o f : 1 . O r i e n t a t i o n o f t h e b o r e h o l e (assumed c o n s t a n t a l o n g l e n g t h ) ; . 2 . A n g l e between a x i s o f c o r e and f o l i a t i o n p l a n e a t t h e t e s t l o c a t i o n ( o b t a i n e d f r o m d r i l l l o g ) . 3 . A n assumed s t r i k e f o r t h e f o l i a t i o n p l a n e s w h i c h was a p p r o p r i a t e f o r t h e p a r t i c u l a r b o r e h o l e ( e x t r a p o l a t e d f r o m mapping o f t h e e x p l o r a t o r y d r i f t ) . 4 . O r i e n t a t i o n o f t he Goodman J a c k i n t h e b o r e h o l e . P o i n t s 1 and 2 c o u l d be d e t e r m i n e d q u i t e a c c u r a t e l y . In s p i t e o f t h e o v e r a l l c o n s i s t e n t s t r i k e d i r e c t i o n a t t h e t e s t s i t e , l o c a l i r r e g u l a r -i t i e s d i d o c c u r . Thus p o i n t 3 i n t r o d u c e d most o f t h e e r r o r i n t o t h e a n a l y s i s . The Goodman J a c k was o r i e n t e d i n t h e b o r e h o l e by r o t a t i n g t h e i n s e r t i o n r o d s i n s u c h a way t h a t an o r i e n t a t i o n c o n v e n t i o n was m a i n t a i n e d w i t h t h e e x p l o r a t o r y d r i f t ( s e e F i g u r e 8 ) . Thus an e r r o r o f a b o u t 5 d e g r e e s c o u l d be i n t r o d u c e d by p o i n t 4 b u t i n t h e m a j o r i t y o f c a s e s w o u l d be much l e s s t h a n p o i n t 3 . These f o u r p o i n t s o f d a t a were a n a l y z e d by s t e r o g r a p h i c p r o -j e c t i o n t o d e t e r m i n e t h e s p a t i a l a r r a n g e m e n t o f l o a d i n g d i r e c t i o n s and f o l i a t i o n p l a n e s . T h i s method i s i l l u s t r a t e d by example i n A p p e n d i x 4 . The c o m p l e t e r e s u l t s o f t h e j a c k t e s t i n g a r e p r e s e n t e d i n A p p e n d i x 5 . These r e s u l t s a r e now a n a l y z e d i n t e rms o f s p e c i f i c r o c k t y p e . 77 1 . Q u a r t z i t e G n e i s s T h i r t y Goodman J a c k t e s t s were c a r r i e d o u t i n t h e q u a r t z i t e g n e i s s . F i g u r e s 3 3 , 34 and 35 a r e s t r e s s - d e f o r m a t i o n c u r v e s t h a t i l l u s t r a t e t h e r a n g e o f t h e q u a r t z i t e g n e i s s b e h a v i o r . F i g u r e s 33 and 34 i l l u s t r a t e t h e a v e r a g e d e f o r m a t i o n c h a r a c t e r -i s t i c s o f t h e g n e i s s . The c u r v e s e x h i b i t l i n e a r i t y a f t e r t h e f i r s t l o a d i n c r e m e n t s , p a r t i c u l a r l y on s e c o n d and s u b s e q u e n t l o a d i n g c y c l e s . Permanent d e f o r m a t i o n s a r e s i g n i f i c a n t , a p p r o a c h i n g 40% f o r t h e t o t a l t e s t l o a d i n g . The c o i n c i d e n c e o f s e c o n d and s u b s e q u e n t l o a d i n g l o o p s i n d i c a t e s t h e d e f o r m a t i o n i s e l a s t i c a f t e r t h e f i r s t c y c l e . A c t u a l h y s t e r e s i s e f f e c t s a r e g e n e r a l l y i n s i g n i f i c a n t when t h e e f f e c t o f t r a n s d u c e r b a c k l a s h i s e l i m i n a t e d . F i g u r e 35 i l l u s t r a t e s q u a r t z i t e g n e i s s b e h a v i o u r w h i c h d e v i a t e s f rom t h e n o r m a l . The n o t e w o r t h y f e a t u r e s o f t h i s g r a p h a r e t h a t s i g n i f i c a n t i n e l a s t i c d e f o r m a t i o n o c c u r s on b o t h l o a d i n g c y c l e s and t h a t t h e h y s t e r e s i s l o s s e s a r e g r e a t e r t h a n n o r m a l . D i s t r i b u t i o n d i a g r a m s f o r t h e f i r s t and s e c o n d c y c l e w o r k i n g modulus a r e shown i n F i g u r e 3 6 . The s i g n i f i c a n t f e a t u r e s o f t h e s e d i a g r a m s a r e as f o l l o w s : 1 . F i r s t c y c l e w o r k i n g m o d u l u s : mean = 1 . 9 5 x 1 0 6 s t a n d a r d d e v i a t i o n '= 0 . 3 8 x 10^ c o e f f i c i e n t o f v a r i a t i o n = 19% H o l e No. Depth _ N X 8 5 . 0 f t . Goodman J a c k T e s t i n g APPLIED LOAD v s . DIAMETRAL BORE HOLE DEFORMATION O r i e n t a t i o n 90J Rock Type g u a r to O -s_ Z2 CO to CD s-3 CO •a 1 0 , 0 0 0 9 , 0 0 0 8 , 0 0 0 7 , 0 0 0 6 , 0 0 0 5 ,000 4 , 0 0 0 3 , 0 0 0 2 , 0 0 0 1 ,000 0 F i r s t c y c l e Second c y c l e T h i r d c y c l e g n e i s s -/ *r / 'f 1 / '/1• -/ // r / / ' / p i / '* hi A n •> m - Ml M *i / */ It -/ ' / / If / */ / If / ;'l t li l*i hi hi hi l*\\ - / 1 / *i X *M X */ / ft X */ in hi lil ill til Mi If If \\ r Tf j X */ ht X it h* // / * ff / 1 / / / X '/ J If X '/ / y i i i i i i i i 1 1 1 1 1 I 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 L O c -5 ro C O C O 5 . 0 1 0 . 0 1 5 . 0 2 0 . 0 2 5 . 0 - 3 , 3 0 . 0 3 5 . 0 4 0 . 0 T o t a l D e f l e c t i o n ( i n c h x 10 ) H o l e No. Depth NX - 7 5£LQ f t . Goodman J a c k T e s t i n g APPLIED LOAD v s . DIAMETRAL BORE HOLE DEFORMATION O r i e n t a t i o n 90c CO to CD S-s-\"D 10 ,000 9 , 0 0 0 8 , 0 0 0 7 , 0 0 0 6 , 0 0 0 5 , 0 0 0 4 , 0 0 0 3 , 0 0 0 2 , 0 0 0 1 ,000 0 F i r s t c y c l e .Second c y c l e T h i r d c y c l e Rock Type quar g n e i s s 5 . 0 1 0 . 0 1 5 . 0 2 0 . 0 2 5 . 0 _ 3 T o t a l D e f l e c t i o n ( i n c h x 10 ) --MSA Ml //nil - /I - // 1 /// II -/ '/ i */ 9 III i ii I'/ / ' / -/ t/ / '/ / */ M */ W */ M 1 / f */ TTJ / '/ / '/ / */ / '/ / '/ / fi III -/ '} / // / If '/ If fr • !/ / *t / */ / */ '/ '/ s*y */ x *X >/ SsX if A> */ / i i i i i i > I 1 i i i i 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 i i i i 3 0 . 0 3 5 . 0 CO g ro C O 4 0 . 0 C O H o l e No. Depth NX - 3 QD.n f t . Goodman J a c k T e s t i n g APPLIED LOAD v s . DIAMETRAL BORE HOLE DEFORMATION O r i e n t a t i o n , Rock Type qui CO Q. CD s-=3 CO oo CD S_ O -3 -a >> F i r s t c y c l e _Second c y c l e T h i r d c y c l e g n e i s s •j CD CO cn 5 . 0 1 0 . 0 1 5 . 0 2 0 . 0 2 5 . 0 T o t a l D e f l e c t i o n ( i n c h x 1 0 \" 3 ) 3 0 . 0 3 5 . 0 4 0 . 0 co o F i r s t C y c l e W o r k i n g Modu lus F i g u r e 36 15 10 F r e q u e n c y 0 mean 1 . 9 5 x 1 0 6 7mode = 2 . 2 0 x 10 30 R v a l u e s ) J I I _ L 0 . 0 0 . 4 Q.8 1 . 2 1 .6 2 . 0 2 . 4 2 . 8 3 . 2 3 . 6 4 . 0 4 . 4 4 . 8 Modulus ( p s i x 10 ) Second C y c l e W o r k i n g Modulus 15 10 F r e q u e n c y 0 mode = 2 . 2 0 x 10 30; ; v a l ues mean = 2 . 4 9 x 10( 0 . 0 0 . 4 0 . 8 1 .2 l i ' 6 2 . 0 2 . 4 2 . 8 3 . 2 3 . 6 4 . 0 4 . 4 4 . 8 81 Modulus ( p s i x 10 ) FREQUENCY'HISTOGRAMS FOR GOODMAN JACK TESTS IN QUARTZITE GNEISS 82 2 . Second c y c l e w o r k i n g m o d u l u s : mean = 2 . 4 9 x 1 0 6 s t a n d a r d d e v i a t i o n = 0 . 4 7 x 10 c o e f f i c i e n t o f v a r i a t i o n = 19% 3 . The d i s t r i b u t i o n s a r e d e f i n i t e l y skewed i n o p p o s i t e d i r e c t i o n s . The l o w e r f i r s t c y c l e modulus i s t o be e x p e c t e d s i n c e i t p r o b a b l y r e -f l e c t s i n e l a s t i c d e f o r m a t i o n s u c h as t h e c l o s i n g o f c r a c k s o r s e a t i n g o f t h e j a c k . The d i f f e r e n c e i n shape o f t h e d i s t r i b u t i o n d i a g r a m s i s p r o b a b l y a r e f l e c t i o n o f t h e f a c t t h a t most o f t h e i n e l a s t i c d e f o r m a t i o n o c c u r s d u r i n g t h e f i r s t l o a d i n g c y c l e . Thus a g r e a t e r p r o p o r t i o n o f l o w modu lus v a l u e s o c c u r d u r i n g t h e f i r s t c y c l e t h a n o c c u r f o r t h e s e c o n d c y c l e . T h i s a c c o u n t s f o r t h e p o s i t i v e skewness o f t h e f i r s t c y c l e modu lus v a l u e s and t h e n e g a t i v e s k e w n e s s o f t h e s e c o n d c y c l e v a l u e s . The a n i s o t r o p y d i a g r a m f o r t h e t e s t s c o n d u c t e d i n q u a r t z i t e g n e i s s i s shown i n F i g u r e 3 7 . As p r e v i o u s l y , d e s c r i b e d , hand s a m p l e s o f t h i s r o c k t y p e e x h i b i t e d l i t t l e f o l i a t i o n . However , i n t h e f i e l d , s m a l l d i s c o n t i n u o u s s c h i s t l a y e r s o f t e n o c c u r r e d w i t h i n t h e g n e i s s . The f o l i a t i o n a n g l e t h u s r e f e r s t o t h e l a y e r i n g o f t h e r o c k c o m p l e x and no t s p e c i f i c a l l y t o f o l i a t i o n w i t h i n t h e g n e i s s . The f i t t e d r e g r e s s i o n l i n e i n F i g u r e 37 has a l o w c o r r e l a t i o n c o e f f i c i e n t . The l a c k o f c o r r e l a t i o n o f t h e a n i s o t r o p y d i a g r a m has two p o s s i b l e e x p l a n a t i o n s . F i r s t l y , t h e q u a r t z i t e g n e i s s may n o t c o n t a i n r e p r e s e n t a t i v e l a y e r i n g i n t h e vo lume o f r o c k a f f e c t e d by t h e Goodman J a c k . T h u s , t h e r e i s no c l e a r l y d e f i n e d a n i s o t r o p y . A s e c o n d p o s s i b l e r e a s o n i s t h a t t h e d e t e r m i n a t i o n o f t h e f o l i a t i o n a n g l e i s t o o i m p r e c i s e . The in situ a n i s o t r o p y i s ANISOTROPY OF THE QUARTZITE GNEISS AS REFLECTED BY THE GOODMAN JACK Second C y c l e W o r k i n g Modulus ( p s i x 1 0 6 ) 3 . 8 3 . 4 3 . 0 2 . 6 2 . 2 1 .8 1 .4 • 1 •• • • • • • • • • • • ******* • • • • • • • **** • — ~ ~ — R e g r ^ CO e s s i o n 1 r r e l a t i o i n e , i c o e f f i — • 0 10 20 30 40 50 60 F o l i a t i o n A n g l e ( d e g r e e s ) 70 80 90 84 a n a l y z e d more t h o r o u g h l y f o r t h e q u a r t z f e l d s p a r s c h i s t t o f o l l o w . The in situ e l a s t i c r e c o v e r y o f t h e q u a r t z i t e g n e i s s a v e r a g e d 60% f o r t h e f i r s t two l o a d i n g c y c l e s . The e l a s t i c r e c o v e r y on t h e s e c o n d c y c l e a v e r a g e d 96%. In s p i t e o f t h e a p p r o x i m a t e c a l c u l a t i o n o f t h e e l a s t i c r e c o v e r y , t h e s e r e s u l t s a r e s i g n i f i c a n t . The permanent d e f o r m -a t i o n f o r t h e in situ q u a r t z i t e g n e i s s i s q u i t e l a r g e . However , l o a d i n g c y c l e s a f t e r t h e f i r s t have n e a r e l a s t i c d e f o r m a t i o n . The r a t i o o f t h e w o r k i n g modu lus t o s e c a n t modu lus a v e r a g e s 1 . 4 8 t o 2 . 5 4 so t h a t t h e p r e s e n c e o f d i s c o n t i n u i t i e s w i t h i n t h e g n e i s s i s q u i t e v a r i a b l e . These r e s u l t s have more s i g n i f i c a n c e when compared t o o t h e r r o c k t y p e s . 2 . Q u a r t z F e l d s p a r S c h i s t F i g u r e s 38 and 39 show d e f o r m a t i o n c u r v e s r e p r e s e n t a t i v e o f t h e b e h a v i o u r o f t h e 61 t e s t s c a r r i e d o u t i n q u a r t z f e l d s p a r s c h i s t . The n o t a b l e c h a r a c t e r i s t i c s o f t h e s e c u r v e s a r e t h e l i n e a r i t y and s m a l l permanent d e f o r m a t i o n s a f t e r t h e f i r s t l o a d i n g c y c l e . The h y s t e r e s i s e x h i b i t e d by F i g u r e 38 i s t h e normal w h i l e t h a t o f F i g u r e 39 i s a d e v i a t i o n . T h i s l a t t e r f i g u r e i l l u s t r a t e s t h e e f f e c t o f t h e f r e e p l a y i n t h e t r a n s d u c e r s when t h e d i r e c t i o n o f l o a d i n g i s c h a n g e d . The f r e e p l a y r e s u l t s i n a t r a p e z o i d a l - s h a p e d l o o p i n d i c a t i n g g r e a t e r h y s t e r e s i s l o s s e s t h a n a c t u a l l y o c c u r . T h i s f e a t u r e i s n o t i c e d i n most o f t h e Goodman J a c k d e f o r m a t i o n c u r v e s t o an e x t e n t d e p e n d e n t on t h e d e f o r m a t i o n c h a r a c t e r i s t i c s o f t h e r o c k . An e x t r e m e i n t h e b e h a v i o u r o f t h e q u a r t z f e l d s p a r s c h i s t i s shown i n F i g u r e 4 0 . The r o c k a t t h i s l o c a t i o n e x h i b i t s a f a i r l y H o l e No. Depth NX - 12 7 0 . 0 f t . Goodman J a c k T e s t i n g APPLIED LOAD v s . DIAMETRAL BORE HOLE DEFORMATION oo CD s~ 3 00 oo CD s-u 3 c a £->> 1 0 , 0 0 0 9 , 0 0 0 8 , 0 0 0 7 ,000 6 , 0 0 0 5 ,000 4 , 0 0 0 3 , 0 0 0 2 , 0 0 0 1 ,000 0 F i r s t c y c l e Second c y c l e .. O r i e n t a t i o n Rock Type T h i r d c y c l e 90c s c h i s t - A>-, '1 i -f t f » f i f l f » f t -/ * / t f t m / * I ft It /•' /' - / ' ' /• m * L f t g M * r f t m It m f t A f t m f t m - x * M t f 1 f 1 J * f t f t £ i £ t f -r r/ t f * f » M 1 f t / t / i f i / t -/ i / J * f t * Jr 0 M - / § Jr i J gr i jf I S f 1 — f ' M7 t ft 1 f f I 1 1 1 1 1 1 1 I 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 I 1 1 1 1 1 1 1 5 . 0 1 0 . 0 1 5 . 0 2 0 . 0 2 5 . 0 U3 -s co 3 0 . 0 3 5 . 0 40.0 2n 14s p a r T o t a l D e f l e c t i o n ( i n c h x 10\" ) H o l e No. Depth cn Q. QJ s--3 in cn CD J-O-ro S--a NX - 12 Goodman J a c k T e s t i n g O r i e n t a t i o n 7 5 . 0 f t . APPLIED LOAD v s . DIAMETRAL BORE HOLE DEFORMATION F i r s t c y c l e Second c y c l e T h i r d c y c l e 0 C 1 0 , 0 0 0 9 , 0 0 0 8 , 0 0 0 7 ,000 6 , 0 0 0 5 ,000 4 , 0 0 0 3 , 0 0 0 2 , 0 0 0 1 ,000 0 Rock Type q u a r t z f e l d s p a r s c h i s t fl - M */ y */ * */ /// t r - / / / \\ ' / 1 Ss 1 I - f * / / <*'/ / / / 1'l I * /// / 1 / 1*1 -/ // i 1 1 / 1*1 / 1 / i l l 1*1 mil mil -r V 1 ' / < / / / # / mil 1 * /// /// -1 f 1 • 1 r * X * / g t / f * / / * / * / 1 1 1 1 f I J *' X - / Syr 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 i i i > 5 . 0 1 0 . 0 1 5 . 0 2 0 . 0 2 5 . 0 _ o T o t a l D e f l e c t i o n ( i n c h x 10 ) 3 0 . 0 3 5 . 0 C O ro GO C O 4 0 . 0 oo cn H o l e No. NX - 20 Goodman J a c k T e s t i n g O r i e n t a t i o n 01 0 5 . 0 1 0 . 0 1 5 . 0 2 0 . 0 2 5 . 0 3 0 . 0 3 5 . 0 4 0 . 0 23 T o t a l D e f l e c t i o n ( i n c h x 1 0 \" 3 ) l i n e a r s t r e s s - d e f o r m a t i o n c u r v e y e t undergoes v e r y l a r g e permanent d e f o r m a t i o n s . A p o s s i b l e e x p l a n a t i o n i s t h a t t h e j a c k l o a d i n g i s c a u s i n g r o c k movement a l o n g a p r e - e x i s t i n g f r a c t u r e p l a n e . Rock b e h a v i o u r o f t h i s t y p e was f o u n d f o r t h e t h r e e o r i e n t a t i o n s o f o n l y one t e s t l o c a t i o n . D i s t r i b u t i o n d i a g r a m s f o r t h e w o r k i n g modulus o f t h e f i r s t , s e c o n d and t h i r d c y c l e s a r e shown i n F i g u r e s 41 and 4 2 . The f o l l o w i n g p o i n t s a r e i l l u s t r a t e d by t h e s e d i a g r a m s : 1 . F i r s t c y c l e w o r k i n g m o d u l u s : mean = 1 .46 x 1 0 6 s t a n d a r d d e v i a t i o n = 0 . 3 2 x 10^ c o e f f i c i e n t o f v a r i a t i o n = 22% 2 . Second c y c l e w o r k i n g m o d u l u s : mean = 1 .92 x 1 0 6 s t a n d a r d d e v i a t i o n = 0 . 4 3 x 1 0 6 c o e f f i c i e n t o f v a r i a t i o n = 22% 3 . T h i r d c y c l e w o r k i n g m o d u l u s : mean = 2 . 0 0 x 1 0 6 s t a n d a r d d e v i a t i o n = 0 . 4 5 x 10 c o e f f i c i e n t o f v a r i a t i o n = 23% 4 . A l l t h r e e d i s t r i b u t i o n s , b u t p a r t i c u l a r l y t h a t f o r t h e s e c o n d c y c l e , a p p r o a c h t h e normal d i s t r i b u t i o n . T h i s i s g r a p h i c a l l y shown by t h e p l o t on normal p r o b a b i l i t y p a p e r , F i g u r e 4 3 . On t h i s p a p e r a normal d i s t r i b u t i o n p l o t s as a s t r a i g h t l i n e . As f o r t h e t e s t s i n q u a r t z i t e g n e i s s , t h e a v e r a g e w o r k i n g modulus f o r t h e s e c o n d c y c l e i s s i g n i f i c a n t l y l a r g e r t h a n t h a t o f t h e f i r s t c y c l e . How-89 F r e q u e n c y F i g u r e 41 F i r s t C y c l e W o r k i n g Modulus 30 20 10 mode: : 1 .40 x 10 ' mean = 1 .46 x 10* J i L 61 v a l u e s J L 0 0 . 0 0 . 4 0 . 8 1 . 2 1 . 6 2 . 0 2 . 4 2 . 8 3 . 2 3 . 6 4 . 0 4 . 4 4 . 8 Modulus ( p s i x 10 ) F r e q u e n c y 30 Second C y c l e W o r k i n g Modulus 20 10 mode = 1 .80 x 10* 0\" L LI mean = 1 .92 x 10 59 v a l u e s mm i L 0 . 0 0 . 4 0 . 8 1 . 2 1 .6 2 . 0 2 . 4 2 . 8 3 . 2 3 . 6 4 . 0 4 . 4 4 . 8 Modu lus ( p s i x 10 ) FREQUENCY HISTOGRAMS FOR GOODMAN JACK TESTS IN QUARTZ FELDSPAR SCHIST 90 F i g u r e 42 T h i r d C y c l e W o r k i n g Modulus 20 F r e q u e n c y 15 10 0 mean = , 2 . 0 q x W mode = 2 . 2 0 x 10 46 v a l u e s J i I J L J L 0 . 0 0 . 4 0 . 8 1 . 2 1 .6 2 . 0 2 . 4 2 . 8 3 . 2 3 . 6 4 : 0 4 . 4 4 . 8 Modulus ( p s i x 10 ) FREQUENCY HISTOGRAM FOR GOODMAN JACK TESTS IN QUARTZ FELDSPAR SCHIST F i g u r e 43 91 FREQUENCY DISTRIBUTION OF SECOND CYCLE WORKING MODULUS FOR QUARTZ FELDSPAR SCHIST 99 98 95 90 /• 80 C u m u l a t i v e D * 70 P e r c e n t 60 50 40 30 20 10 / • / K / 2 1 i I i I i i i i i i i i 1 . 0 2 . 0 3 . 0 4. 0 c Modu lus ( p s i x 10 ) 92 e v e r , t h e v a l u e s f o r t h e s e c o n d and t h i r d c y c l e s a r e a l m o s t i d e n t i c a l . T h i s p o i n t s o u t t h e n e c e s s i t y o f o n l y p e r f o r m i n g two l o a d i n g c y c l e s i n t h i s r o c k t y p e . The f a c t t h a t t h e d i s t r i b u t i o n s a r e v e r y n e a r l y normal must i n d i c a t e t h a t a r e p r e s e n t a t i v e samp le o f t h e s c h i s t was t e s t e d . F i g u r e 44 shows t h e a n i s o t r o p y o f t h e in situ q u a r t z f e l d s p a r s c h i s t . As c a n be seen a g r e a t d e a l o f s c a t t e r i s p r e s e n t i n t h i s p l o t and t h e c o r r e l a t i o n c o e f f i c i e n t f o r t h e f i t t e d r e g r e s s i o n l i n e i s o n l y 0 . 4 4 . The o n l y i n f o r m a t i o n t h a t c a n be o b t a i n e d f r o m t h i s d i a g r a m i s t h e vague g e n e r a l i z a t i o n t h a t t h e h i g h e s t modu lus v a l u e s t e n d t o c o r r e s p o n d t o t h e l o w f o l i a t i o n a n g l e s . The s c a t t e r o f a n i s o t r o p y d i a g r a m c o u l d be due t o t h e f o l l o w i n g : 1 . As shown i n F i g u r e 45 d i f f e r e n t o r i e n t a t i o n s o f t h e j a c k c a n have t h e same l o a d i n g d i r e c t i o n - f o l i a t i o n p l a n e r e l a t i o n -s h i p . F o r e x a m p l e , t h e l o a d i n g c a n be p a r a l l e l t o t h e f o l i a t i o n w h i l e t h e j a c k i t s e l f i s e i t h e r p a r a l l e l o r p e r -p e n d i c u l a r t o t h e f o l i a t i o n . Thus t h e modu lus d e t e r m i n e d by t h e j a c k c o u l d be d e p e n d e n t n o t o n l y on t h e f o l i a t i o n a n g l e b u t a l s o on t h e j a c k o r i e n t a t i o n . 2 . In situ f e a t u r e s s u c h as s t r u c t u r a l d i s c o n t i n u i t i e s o r in situ s t r e s s e s w h i c h c a u s e i n h o m o g e n e i t y i n t h e s c h i s t and t h u s d i s t o r t i o n o f t h e m o d u l u s - f o l i a t i o n a n g l e r e l a t i o n s h i p . 3 . I n a c c u r a c y i n t h e d e t e r m i n a t i o n o f t h e f o l i a t i o n a n g l e . P o i n t 1 was i n v e s t i g a t e d by d i v i d i n g t h e t e s t s a c c o r d i n g t o t h e a n g l e between t h e l o n g a x i s o f t h e j a c k ( i . e . t h e b o r e h o l e ) and ANISOTROPY OF THE QUARTZ FELDSPAR SCHIST AS REFLECTED BY THE GOODMAN JACK A n g l e between b o r e ho i fe; and f o l i a t i o n : • = 0 ° t o 30° , * = 30° t o 60°, += 60° t o 90° Second C y c l e W o r k i n g Modulus ( p s i x 1 0 6 ) 3 . 0 2 . 6 2 . 2 1 .8 1 . 4 1 .0 0 . 6 *** + + + + > r • + • + • • ,. « • T • i • • \\ - + • ~Regress c o r r e i o n l i n e , l a t i o n cc -r = . 44 0 10 20 30 40 50 60 F o l i a t i o n A n g l e ( d e g r e e s ) 70 80 90 t o -s CO F i g u r e 45 94 THREE POSSIBLE ORIENTATIONS OF THE GOODMAN JACK WITH REGARD TO THE DIRECTION OF LOADING AND FOLIATION PLANE J a c k p a r a l l e l t o f o l i a t i o n , l o a d i n g p e r p e n d i c u l a r t o f o l i a t i o n , ( i . e . f o l i a t i o n a n g l e = 90°) J a c k p a r a l l e l t o f o l i a t i o n , l o a d i n g p a r a l l e l t o f o l i a t i o n , ( i . e . f o l i a t i o n a n g l e = 0°) J a c k p e r p e n d i c u l a r t o f o l i a t i o n , l o a d i n g p a r a l l e l t o f o l i a t i o n , ( i c e . f o l i a t i o n a n g l e =J0° ) 95 t h e r o c k s c h i s t o s i t y . R e - e x a m i n a t i o n o f F i g u r e 44 shows t h a t t h i s a n g l e has been d i v i d e d i n t o t h r e e g r o u p s . A l t h o u g h t h e s y m b o l s a r e f a i r l y w e l l g r o u p e d t h e r e i s l i t t l e o v e r l a p o f t e s t s w i t h t h e same f o l i a t i o n a n g l e and d i f f e r e n t j a c k o r i e n t a t i o n s . The dependence o f i n d i c a t e d r o c k a n i s o t r o p y upon o r i e n t a t i o n o f t h e j a c k t h u s r e m a i n s o b s c u r e . P o i n t 2 was i n v e s t i g a t e d by d e t e r m i n i n g t h e v a r i a t i o n o f d e f o r -m a t i o n modu lus e x p r e s s e d as a p e r c e n t a g e o f t h e l o w e s t d e t e r m i n e d v a l u e f o r each t e s t l o c a t i o n . T h i s v a r i a t i o n w o u l d more c l o s e l y r e p r e s e n t t h e e f f e c t o f f o l i a t i o n a n g l e w h i l e n e g a t i n g t h e e f f e c t o f l a r g e s c a l e i n h o m o g e n e i t y i n t h e s c h i s t . I t was f o u n d t h a t t h e v a r i a t i o n i n t h e t h r e e modulus v a l u e s f o r a p a r t i c u l a r t e s t d e p t h r a n g e d f r o m 6% t o 40% and a v e r a g e d 20%. In summary, t h e Goodman J a c k i n d i c a t e s t h a t t h e s c h i s t i s a n i s o t r o p i c . However , t h e e x a c t r e l a t i o n s h i p between modulus and f o l i a t i o n a n g l e i s o b s c u r e w i t h o u t more a c c u r a t e g e o l o g i c c o n t r o l a t t h e t e s t l o c a t i o n s . The e l a s t i c r e c o v e r y o f t h e q u a r t z f e l d s p a r s c h i s t a v e r a g e d 56% f o r t h e f i r s t two l o a d i n g c y c l e s . T h i s means t h a t s i g n i f i c a n t permanent d e f o r m a t i o n o c c u r s i n t h i s r o c k t y p e . F o r t h e s e c o n d c y c l e o n l y , 91% o f t h e d e f o r m a t i o n was r e c o v e r a b l e . Thus i n e l a s t i c b e h a v i o u r i s r e s t r i c t e d t o t h e f i r s t l o a d i n g c y c l e . The a v e r a g e r a t i o o f t h e s e c o n d c y c l e w o r k i n g modu lus t o s e c a n t modulus i s 1 . 5 9 . The s i g n i f i c a n c e o f t h i s r e s u l t w i l l be d e m o n s t r a t e d i n t h e c o m p a r i s o n o f r o c k t y p e s . 96 3 . P e g m a t i t e T w e l v e Goodman J a c k t e s t s were c a r r i e d o u t i n p e g m a t i t e . As f o r t h e l a b o r a t o r y t e s t i n g , f r e q u e n c y h i s t o g r a m s c o u l d n o t be p r e p a r e d f o r t h i s r o c k t y p e . F i g u r e 46 shows a r e p r e s e n t a t i v e d e f o r m a t i o n c u r v e f o r t h e p e g m a t i t e . The m a t e r i a l d i s p l a y s a l i n e a r d e f o r m a t i o n c u r v e and an e l a s t i c r e s p o n s e a f t e r t h e f i r s t l o a d i n g c y c l e . H y s t e r e s i s e f f e c t s a r e g e n e r a l l y i n s i g n i f i c a n t as e x e m p l i f i e d by t h e n a r r o w l o a d - u n l o a d l o o p s . The a v e r a g e f i r s t c y c l e w o r k i n g modulus i s 1 .57 x 10^ p s i w h i l e t h a t o f t h e s e c o n d c y c l e i s 2 . 0 6 x 10^ p s i . The d i f f e r e n c e i s 31%, i n d i c a t i n g t h a t l a r g e i n e l a s t i c d e f o r m a t i o n s a r e o c c u r r i n g i n t h e f i r s t l o a d c y c l e . The a v e r a g e p e r c e n t e l a s t i c r e c o v e r y f o r t h e f i r s t two l o a d i n g c y c l e s i s 59%. F o r t h e s e c o n d c y c l e o n l y , t h i s v a l u e i s 96% r e i n f o r c i n g t h e i n d i c a t i o n a b o v e . 4 . Summary and C o m p a r i s o n o f Goodman J a c k R e s u l t s T h e i r e s u l t s o f t h e Goodman J a c k t e s t i n g a r e summar i zed i n T a b l e 3 . E x a m i n a t i o n o f t h e summar i zed r e s u l t s r e v e a l s t h a t f o r a p a r t i c u l a r modulus t y p e v e r y l i t t l e d i f f e r e n c e e x i s t s between r o c k t y p e s . F o r e x a m p l e , t h e mean s e c o n d c y c l e w o r k i n g modulus f o r q u a r t z i t e g n e i s s i s o n l y 1 . 3 t i m e s t h a t o f t h e q u a r t z f e l d s p a r s c h i s t and 1 . 2 t i m e s t h a t o f p e g m a t i t e . F u r t h e r , t h e s t a n d a r d d e v i a t i o n and r a n g e o f s e c o n d c y c l e w o r k i n g modulus a r e s i m i l a r f o r a l l r o c k t y p e s . H o l e No. NX - 15 Goodman J a c k T e s t i n g O r i e n t a t i o n 90° Depth 6 0 . 0 f t . . _ APPLIED LOAD v s . DIAMETRAL BORE HOLE DEFORMATION Rock T y p e J ^ m a i i t e . F i r s t c y c l e Second c y c l e T h i r d c y c l e 10,000 i r — n n ~ T ~ ~ T ~ ~T~ 0 5 . 0 1 0 . 0 1 5 . 0 2 0 . 0 2 5 . 0 3 0 . 0 3 5 . 0 4 0 . 0 T o t a l D e f l e c t i o n ( i n c h x 10\" 3) 98 TABLE 3 SUMMARY OF GOODMAN JACK RESULTS N o t e : A l l modulus v a l u e s i n p s i x 10^ Q u a r t z P r o p e r t y Q u a r t z i t e G n e i s s F e l d s p a r S c h i s t P e g m a t i t e a . Number o f t e s t s 30 61 12 b. Mean s e c o n d c y c l e s e c a n t modulus 1.71 1 . 2 5 1.41 c . Mean s e c o n d c y c l e r e c o v e r y modulus 2 . 8 6 2 . 2 4 2 . 3 8 d . Mean f i r s t c y c l e w o r k i n g modulus 1 . 9 5 1 .46 1 .57 e . S t a n d a r d d e v i a t i o n o f d 0 . 3 8 0 . 3 2 0 . 3 3 f . C o e f f i c i e n t o f v a r i a t i o n 19% 22% 21% g- Mean s e c o n d c y c l e w o r k i n g modulus 2 . 4 9 1 .92 2 . 0 6 h . S t a n d a r d d e v i a t i o n o f g 0 . 4 7 0 . 4 3 0 . 4 2 i . C o e f f i c i e n t o f v a r i a t i o n 19% 22% 20% j . Range, o f s e c o n d c y c l e w o r k i n g modulus 1 . 6 4 t o 3 . 7 0 0 . 8 7 t o 3 . 1 6 1 .32 t o 2 . 8 0 k. \" x \" * 2 . 7 7 2.11 2 . 3 7 1 . \"y »** 2 . 2 3 1 . 7 6 1.81 m. A n i s o t r o p y I n d e x , A . I . 22% 19% 27% n. % E w ( s e c o n d c y c l e ) g r e a t e r E ( f i r s t c y c l e ) 28% 31% 31% 0. A v e r a g e % e l a s t i c r e c o v e r y f o r two c y c l e s 60% 56% 59% P- A v e r a g e % e l a s t i c r e c o v e r y f o r s e c o n d c y c l e 96% 91% 96% q . A v e r a g e r a t i o , E /E„ 3 w s 1 .48 1 .59 1 .48 * x mean o f t h e maximum s e c o n d c y c l e w o r k i n g modulus t e s t l o c a t i o n r e g a r d l e s s o f o r i e n t a t i o n v a l u e s a t each ** y mean o f t h e minimum s e c o n d c y c l e w o r k i n g modulus v a l u e s a t e a c h t e s t l o c a t i o n r e g a r d l e s s o f o r i e n t a t i o n 99 To r e d u c e t h e e f f e c t o f r o c k a n i s o t r o p y i n t h e c o m p a r i s o n o f mean modulus v a l u e s , p r o p e r t i e s k and 1 o f T a b l e 3 were c o m p u t e d . These v a l u e s r e p r e s e n t t h e mean o f t h e maximum (k ) o r minimum (1) s e c o n d c y c l e w o r k i n g modulus v a l u e s a t e a c h t e s t l o c a t i o n r e g a r d l e s s ^ o f o r i e n t a t i o n . Note t h a t t h e r a t i o o f q u a r t z i t e g n e i s s t o q u a r t z f e l d s p a r s c h i s t i s 1 . 3 f o r b o t h p r o p e r t i e s k and 1 . The r a t i o s f o r q u a r t z i t e g n e i s s t o p e g m a t i t e a r e b o t h 1 . 2 . I t i s c o n c l u d e d t h a t a l l r o c k t y p e s have modulus v a l u e s t h a t d i f f e r by l e s s t h a n 30%. D i s c o u n t i n g e x t r e m e e x a m p l e s , v e r y l i t t l e v a r i a t i o n i n d e f o r -m a t i o n b e h a v i o u r i s e x h i b i t e d by t h e s t r e s s - d e f o r m a t i o n c u r v e s . A l l r o c k t y p e s show f a i r l y l i n e a r r e s p o n s e a f t e r t h e f i r s t l o a d i n g c y c l e . Permanent d e f o r m a t i o n s a r e s i g n i f i c a n t on t h e f i r s t l o a d i n g b u t e l a s t i c b e h a v i o u r f o l l o w s d u r i n g s u b s e q u e n t l o a d i n g . H y s t e r e s i s l o s s e s a r e low b u t a r e n o t i c e a b l y l a r g e r f o r t h e s c h i s t s t h a n t h e o t h e r two r o c k t y p e s . T h i s p r o b a b l y r e f l e c t s t h e d e f o r m a t i o n o f m i c a c e o u s m i n e r a l s . As d e s c r i b e d i n s e c t i o n s V I . B . l and 2 t h e Goodman J a c k d i d n o t r e f l e c t t h e modulus a n i s o t r o p y f o r t h e s c h i s t o r g n e i s s . A number o f p o s s i b l e r e a s o n s were p r e s e n t e d . However , t o compare t h e r e l a t i v e a n i s o t r o p y o f t h e v a r i o u s r o c k t y p e s an a n i s o t r o p y i n d e x , A . I . , has been d e f i n e d : A . I . = *=X- (100%) m v 1 where x mean o f t h e maximum s e c o n d c y c l e w o r k i n g modulus v a l u e s a t e a c h t e s t l o c a t i o n r e g a r d l e s s o f o r i e n t a t i o n 100 y mean o f t h e minimum s e c o n d c y c l e w o r k i n g modulus v a l u e s a t e a c h t e s t l o c a t i o n r e g a r d l e s s o f o r i e n t a t i o n m mean o f a l l s e c o n d c y c l e w o r k i n g m o d u l i f o r a p a r t i c u l a r r o c k t y p e R e f e r r i n g t o T a b l e 3 t h e A . I . v a l u e s a r e 22%, 19% and 27% f o r t h e q u a r t z i t e g n e i s s , q u a r t z f e l d s p a r s c h i s t and p e g m a t i t e r e s p e c t i v e l y . These i n d e x v a l u r e p r e s e n t n o t o n l y t h e a n i s o t r o p y o f t h e r o c k b u t a l s o p r e f e r e n t i a l r o u g h -ness o f t h e b o r e h o l e and t h e in situ s t r e s s f i e l d . The i n d e x v a l u e s r e p r e s e n t an a p p a r e n t a n i s o t r o p y f o r e a c h r o c k t y p e . Hence i t i s c o n c l u d e d t h a t t h e a p p a r e n t a n i s o t r o p i c s a r e s i g n i f i c a n t , though n o t a b s o l u t e , and a r e s i m i l a r f o r t h e t h r e e r o c k t y p e s . C o m p a r i s o n o f p r o p e r t i e s n t h r o u g h q o f T a b l e 3 r e v e a l s l i t t l e d i f f e r e n c e between r o c k t y p e s . The p e r c e n t a g e t h a t t h e mean s e c o n d c y c l e w o r k i n g modulus i s g r e a t e r t h a n t h a t o f t h e f i r s t c y c l e a v e r a g e s 30%. E l a s t i c r e c o v e r y f o r t h e f i r s t two l o a d i n g c y c l e s i s f a i r l y l o w , a b o u t 60%. For t h e s e c o n d c y c l e o n l y , t h e e l a s t i c r e c o v e r y i s g r e a t e r t h a n 90% f o r a l l r o c k t y p e s . In b o t h c a s e s , t h e r e c o v e r y f o r t h e s c h i s t i s s l i g h t l y l e s s , i n d i c a t i n g more permanent d e f o r m a t i o n i n t h i s r o c k t y p e . The r a t i o , E w / E s , i s s l i g h t l y l a r g e r f o r t h e s c h i s t w h i l e t h e g n e i s s and p e g m a t i t e a r e t h e same. As p r e v i o u s l y e x p l a i n e d , t h e f a i l u r e t o r e c o r d t h e d e f o r m a t i o n f o r t h e f i r s t l o a d i n c r e m e n t c a n r e d u c e t h e o b s e r v e d r a t i o d i f f e r e n c e between r o c k t y p e s . However i t i s f e l t t h a t t h e g r e a t e r r a t i o , E w / E s > f o r t h e q u a r t z f e l d s p a r s c h i s t i s s i g n i f i c a n t . T h i s i n d i c a t e s t h e s c h i s t s undergo a g r e a t e r amount o f i n e l a s t i c d e f o r m a t i o n w h i c h c o u l d be c a u s e d by : 101 (a ) The c l o s u r e o f f r a c t u r e s o r f o l i a t i o n i n t h e d e s t r e s s e d zone i m m e d i a t e l y a r o u n d t h e b o r e h o l e . (b) The d e f o r m a t i o n o f a s p e r i t i e s on t h e b o r e h o l e w a l l s a s s u m i n g t h e h o l e s i n s c h i s t were r o u g h e r t h a n t h o s e i n t h e o t h e r r o c k t y p e s . V i s u a l e x a m i n a t i o n o f r o c k c o r e s c o n f i r m t h i s a s s u m p t i o n i n t h a t t h e c o r e e x h i b i t e d marked d i a m e t e r f l u c t u a t i o n s as w e l l as a r o u g h p i t t e d n a t u r e d e p e n d i n g on t h e f o l i a t i o n o r i e n t a t i o n . In summary, t h e Goodman J a c k has shown t h a t t h e t h r e e r o c k t y p e s have s i m i l a r in situ d e f o r m a t i o n p r o p e r t i e s . C. P l a t e L o a d i n g T e s t s The r e s u l t s o f t h e p l a t e l o a d i n g t e s t s , based on t h e c o n c l u s i o n s r e a c h e d by company p e r f o r m i n g t h e m , w i l l be p r e s e n t e d i n l e s s d e t a i l t h a n t h e p r e v i o u s programmes. Measurements were t a k e n on o p p o s i t e w a l l s a t e a c h o f t h e s i x t e s t l o c a t i o n s y i e l d i n g t w e l v e s e t s o f r e s u l t s . However , t h e m o r t a r cap f a i l e d a t one l o c a t i o n so t h a t e l e v e n s e t s o f u s a b l e d a t a were o b t a i n e d . The c o m p l e t e s e t o f r e s u l t s a r e shown i n T a b l e 4 . Itote t h a t t h e q u a r t z f e l d s p a r s c h i s t i s r e f e r r e d t o as b i o t i t e s c h i s t w h i c h i s n o t i n d i c a t i v e o f any c o m p o s i t i o n a l d i f f e r e n c e b u t r a t h e r r e p r e s e n t s mapping by d i f f e r e n t g e o l o g i s t s . S i m i l a r l y , t h e q u a r t z i t e g n e i s s i s r e f e r r e d t o as g r a n i t i c g n e i s s . F i g u r e s 47 and 48 show l o a d d e f o r m a t i o n c u r v e s f o r t h e g n e i s s and s c h i s t r e s p e c t i v e l y . These c u r v e s a r e r e p r e s e n t a t i v e o f t h e r o c k 102 TABLE 4 RESULTS OF PLATE LOADING TESTS * VHV = v e r y h i g h v a l u e ** T h i s v a l u e n o t used A l l modulus v a l u e s x 1 0 6 p s i T e s t Number O r i e n t a t i o n M o d u l i o f E l a s t i c i t y P e r c e n t E l a s t i c R e c o v e r y E s E w E r Comp le te T e s t L a s t C y c l e E / E w s F o r g r a n i t i c g n e i s s : P L - 3 Ram h o r i z o n t a l 2 . 20 3 . 8 5 1 2 . 4 0 17 58 1 . 7 5 P L - 3 B u t t h o r i z o n t a l 2 . 20 3 . 8 7 1 2 . 4 0 17 45 1 . 7 6 P L - 4 Ram v e r t i c a l 2 . 25 2 . 6 5 4 . 5 4 41 67 1 .18 P L - 5 Ram v e r t i c a l 2 . 61 2 . 9 7 9 . 1 2 29 62 1 .14 P L - 5 B u t t v e r t i c a l 1 . 09 1 . 2 5 2.21 47 90 1 . 1 5 P L - 6 Ram h o r i z o n t a l 5 . 62 6 . 9 5 VHV* 31 100 1 . 2 3 P L - 6 B u t t h o r i z o n t a l 1 2 . 18 7 . 0 8 VHV - - -G n e i s s A v e r a g e s : 4 . 02 4 . 0 9 8 . 1 3 30 70 1 .37 F o r b i o t i t e s c h i s t : P L - 1 Ram h o r i z o n t a l 0 . 90 1 .29 2 . 5 3 35 93 1 . 4 3 P L - 1 B u t t h o r i z o n t a l 0 . 79 0.71 3 . 7 8 20 53 0 . 8 9 * * P L - 2 Ram v e r t i c a l 0 . 23 0 . 3 0 0 . 6 2 36 66 1 .30 P L - 4 B u t t v e r t i c a l 0. 46 0 . 6 0 2.21 23 49 1 . 3 0 S c h i s t A v e r a g e s : 0 . 60 0 . 7 3 2 . 2 8 29 65 1 . 3 4 P l a t e D e f l e c t i o n ( i n c h ) 105 b e h a v i o u r d u r i n g t h e p l a t e l o a d t e s t i n g . S e v e r a l d i f f e r e n c e s between the g n e i s s and s c h i s t r o c k t y p e s a r e t o be n o t e d . The most o b v i o u s d i f f e r e n c e i s t h a t t h e s c h i s t s undergo much l a r g e r , d e f o r m a t i o n s , t h u s t h e i r l o w e r m o d u l u s . The g n e i s s e s show s i g n i f i c a n t l y l e s s h y s t e r e s i s l o s s as e x p r e s s e d by t i g h t n e s s o f t h e l o a d - u n l o a d l o o p s . B o t h r o c k t y p e s e x h i b i t l i n e a r d e f o r m a t i o n c u r v e s on t h e l o a d i n g p o r t i o n o f t h e c y c l e s . A l s o , t h e permanent d e f o r m a t i o n f o r e a c h r o c k t y p e i s q u i t e h i g h . On t h e b a s i s o f t h e l o a d - d e f o r m a t i o n c u r v e s a l o n e , t h e g n e i s s and s c h i s t b e h a v i o u r have been w e l l d i f f e r e n t i a t e d by t h e p l a t e l o a d t e s t s . E x a m i n i n g t h e a v e r a g e d r e s u l t s o f T a b l e 4 r e v e a l s t h a t a l l t h r e e modulus v a l u e s f o r t h e g n e i s s a r e v e r y much h i g h e r t h a n t h o s e o f t h e s c h i s t . The a v e r a g e w o r k i n g modulus f o r t h e g n e i s s i s 5 . 6 t i m e s t h a t o f t h e s c h i s t . T h i s i n d i c a t e s t h a t t h e in situ r o c k t y p e s have v e r y d i s t i n c t i v e d e f o r m a t i o n p r o p e r t i e s . B o t h r o c k t y p e s e x h i b i t a l a r g e r a n g e i n w o r k i n g m o d u l u s ; t h e s c h i s t f r o m 0 . 3 0 t o 1 .29 x 10^ p s i and t h e g n e i s s f rom 1 . 2 5 t o 7 . 0 8 x 10^ p s i . However , t h e o v e r l a p o f t h e s e r a n g e s i s v e r y s m a l l . The d i s t r i b u t i o n o f t h e r e s u l t s o f t h e p l a t e l o a d i n g t e s t s can be i n v e s t i g a t e d i n an a p p r o x i m a t e manner , ( s e e Guttman and W i l k s , pp . 2 2 2 - 2 2 3 ) The d i s t r i b u t i o n o f p l a t e l o a d i n g r e s u l t s a r e shown i n F i g u r e 49 on normal p r o b a b i l i t y p a p e r . D i s t i n c t and a p p r o x i m a t e l y normal d i s t r i b u t i o n s a r e i n d i c a t e d f o r t h e two r o c k t y p e s . S i n c e t h e p l a t e l o a d i n g t e s t s were c a r r i e d o u t i n h o r i z o n t a l and v e r t i c a l d i r e c t i o n s w i t h i n the e x p l o r a t o r y t u n n e l , a rough c h e c k on t h e a n i s t r o p y o f t h e r o c k i s p o s s i b l e . The h o r i z o n t a l t e s t s l o a d e d a p p r o x i m a t e l y p a r a l l e l t o t h e r o c k l a y e r i n g w h i l e t h e v e r t i c a l t e s t s l o a d e d n e a r l y p e r p e n d i c u l a r t o i t . 106 F i g u r e 49 FREQUENCY DISTRIBUTIONS FOR THE PLATE LOADING TESTS C u m u l a t i v e P e r c e n t 99 98 95 90 80 70 60 50 40 30 20 10 5 2 1 i i t • i / • f ; • • 1 ( 1 +; • i t > • • t i i • 1 f :* • 0 1 .0 2 . 0 3 . 0 4 . 0 5 . 0 6 . 0 W o r k i n g Modu lus ( p s i x 1 0 6 ) 7 . 0 8 . 0 q u a r t z i t e g n e i s s , q u a r t z f e l d s p a r s c h i s t 107 The a v e r a g e w o r k i n g modu lus f o r t h e g n e i s s l o a d e d p a r a l l e l t o t h e l a y e r i n g i s 5 . 4 4 x 1 0 6 p s i w h i l e t h a t f o r l o a d i n g p e r p e n d i c u l a r t o t h e f o l i a t i o n i s 2 . 2 7 x 10 p s i . The g n e i s s i s t h u s 2 . 4 t i m e s as r i g i d when l o a d e d p a r a l l e l t o t h e r o c k l a y e r i n g . F o r t h e s c h i s t t h e v a l u e s ft fi a r e 1 .00 x 10 p s i and 0 . 4 5 x 10 p s i f o r l o a d i n g p a r a l l e l and p e r p e n d i c u l a r r e s p e c t i v e l y . The s c h i s t i s t h u s 2 . 2 t i m e s as r i g i d when l o a d e d p a r a l l e l t o t h e r o c k l a y e r i n g . The a n i s o t r o p y i n d i c a t e d by t h e p r e c e d i n g r e s u l t s c a n n o t be i n t e r p r e t e d as a r e f l e c t i o n o f r o c k p r o p e r t i e s a l o n e . Due t o t h e e x c a v a -t i o n p r o c e s s a zone o f r o c k v a r i a b l e i n b l a s t damage and s t r e s s c o n c e n -t r a t i o n s u r r o u n d s t h e d r i f t . The r e l a t i v e i m p o r t a n c e o f t h e s e f a c t o r s on t h e a n i s o t r o p y r e s u l t s i s d i f f i c u l t t o p r e d i c t . The r a t h e r s m a l l e l a s t i c r e c o v e r i e s shown i n T a b l e 4 a r e s i g n i f i c a n t t o t h e in situ b e h a v i o u r o f t h e two r o c k t y p e s . However , i t i s f e l t t h a t t h e t r u e in situ e l a s t i c r e s p o n s e i s s i g n i f i c a n t l y g r e a t e r t h a n t h a t i n d i c a t e d by t h e p l a t e l o a d i n g t e s t s . The r e a s o n b e i n g t h a t t h e d i a l gauge s y s t e m i s r e f l e c t i n g n o t o n l y t h e r e s p o n s e o f t h e r o c k f a b r i c b u t a l s o t h e d e f o r m a t i o n o f t h e b l a s t i n d u c e d m i c r o -f r a c t u r e s and t h e d e f o r m a t i o n o f t h e s u l p h u r p a d . T h i s i s s u p p o r t e d by t h e f a c t t h a t t h e g n e i s s and s c h i s t have n e a r l y i d e n t i c a l e l a s t i c r e c o v e r i e s . Thus t h e l a r g e permanent d e f o r m a t i o n s must be c o n s i d e r e d a f u n c t i o n o f b o t h t h e t e s t i n g method and t h e in situ r o c k b e h a v i o u r . To summar i ze t h e p l a t e l o a d i n g t e s t s , i t c a n be s a i d t h a t t h e two r o c k t y p e s have v e r y d i s t i n c t i v e in situ d e f o r m a t i o n m o d u l i . 108 CHAPTER V I I COMPARISON OF TESTING TECHNIQUES A . M a g n i t u d e o f M o d u l i 1 . F a c t o r s R e l e v e n t t o C o m p a r i s o n F i g u r e 50 i l l u s t r a t e s b o t h t h e r a n g e and mean o f t h e s e c o n d c y c l e w o r k i n g modulus f o r t h e t h r e e t e s t i n g programmes. Two p o i n t s must be k e p t i n m ind when i n t e r p r e t i n g t h i s f i g u r e , t h e r o c k q u a l i t y and t h e s i z e o f t h e zone o f i n f l u e n c e o f t h e t e s t . The r o c k q u a l i t y and i t s v a r i a b i l i t y w i l l a f f e c t b o t h t h e range and mean o f t h e modulus v a l u e s . The e x p e c t e d r o c k q u a l i t y f o r e a c h t e s t i n g programme c a n be summar i zed as f o l l o w s : 1 . L a b o r a t o r y t e s t s : T h e s e t e s t s a r e c a r r i e d o u t on sound p i e c e s o f r o c k c o r e w h i c h t h e p r o c e s s e s o f d r i l l i n g , h a n d l i n g and p r e p a r a t i o n have n o t been a b l e t o d e s t r o y . The modulus v a l u e s s h o u l d t e n d t o be h i g h e r and have a l o w r a n g e . 2 . Goodman J a c k t e s t s : The random l o c a t i o n o f t e s t s r e l a t i v e t o g e o l o g i c f e a t u r e s s h o u l d r e s u l t i n a w i d e r a n g e o f modulus r e s u l t s . 3 . P l a t e l o a d i n g t e s t s : These t e s t s a r e p e r f o r m e d i n a zone o f r o c k s u s c e p t i b l e t o d e s t r e s s i n g and b l a s t damage. Modu lus v a l u e s s h o u l d e x h i b i t a w i d e r a n g e and c o u l d t e n d t o be c o n -s i s t e n t l y l o w e r t h a n o t h e r t e s t i n g m e t h o d s . 109 . F i g u r e 50 MODULUS RANGE FOR VARIOUS TESTING METHODS - q u a r t z i t e g n e i s s 'C'$& - p e g m a t i t e - q u a r t z f e l d s p a r s c h i s t T mean v a l u e — r - — i — L a b o r a t o r y T e s t s 23 t e s t s 42 t e s t s 6 t e s t s \\ —J — / 30 t e s t s 12 t e s t s 61 t e s t s Goodman J a c k T e s t s 4 t e s t s P l a t e L o a d i n g Tests I 7 t e s t s 8 10 11 W o r k i n g Modu lus ( p s i x 10 ) n o The s e c o n d p o i n t t o c o n s i d e r i s t h e vo lume o f r o c k i n f l u e n c e d by a p a r t i c u l a r t e s t i n g method . F o r t h e t h r e e t e s t i n g methods t h e f o l l o w i n g r o c k vo lumes w o u l d be i n f l u e n c e d : 1 . L a b o r a t o r y t e s t s : f r a c t i o n o f a c u b i c f o o t . 2 . Goodman J a c k t e s t s : a p p r o x i m a t e l y one c u b i c f o o t . 3 . P l a t e l o a d i n g t e s t s : a p p r o x i m a t e l y two c u b i c f e e t . The d e g r e e t o w h i c h a r e p r e s e n t a t i v e vo lume o f t h e r o c k i s t e s t e d i s known as t h e s c a l e e f f e c t . Many w r i t e r s i n c l u d i n g B u k o v a n s k y [ 3 ] have r e p o r t e d on t h e v a r i a t i o n o f d e f o r m a t i o n modulus w i t h t h e t e c h n i q u e u s e d t o d e t e r m i n e i t . The g e n e r a l c o n c l u s i o n i s t h a t t h e g r e a t e r t h e vo lume o f r o c k t e s t e d t h e l o w e r and more r e p r e s e n t a t i v e t h e modu lus t e n d s t o b e . 2 . O b s e r v a t i o n s on t h e T h r e e Groups o f Modu lus R e s u l t s The modu lus r e s u l t s f o r t h e t h r e e t e s t i n g methods i l l u s t r a t e d i n F i g u r e 50 a r e i n t e r p r e t e d b e a r i n g i n mind t h e r e l e v e n t f a c t o r s o u t l i n e d i n t h e p r e c e d i n g s e c t i o n . On t h i s b a s i s s e v e r a l o b s e r v a t i o n s c a n be made: 1 . As a n t i c i p a t e d t h e l a b o r a t o r y r e s u l t s s h o w i t h e h i g h e s t mean modulus v a l u e s . U n e x p e c t e d l y t h e s e r e s u l t s a l s o show t h e g r e a t e s t r a n g e o f v a l u e s . 2 . The o r d e r o f r o c k t y p e s f r o m h i g h e s t t o l o w e s t modulus i s q u a r t z i t e g n e i s s , p e g m a t i t e , q u a r t z f e l d s p a r s c h i s t , and i s c o n s i s t e n t w i t h i n e a c h t e s t i n g method . On t h e o t h e r hand t h e d i f f e r e n t i a t i o n o f r o c k t y p e b a s e d on modulus i s h i g h l y v a r i a b l e d e p e n d i n g on t h e t e s t i n g method . I l l 3 . The q u a r t z f e l d s p a r s c h i s t modu lus v a l u e s d e c r e a s e w i t h i n -c r e a s i n g t e s t vo lume and t h u s r e f l e c t t h e e n v i s a g e d s c a l e e f f e c t w h i l e t h e q u a r t z i t e g n e i s s v a l u e s do n o t . On t h e b a s i s o f t h e o b s e r v e d r e s u l t s and t h e e x p e c t e d t r e n d s o u t l i n e d i n s e c t i o n V I I . A . 1 . i t i s i n f e r r e d t h a t t h e t h r e e t e s t i n g programmes have p r o v i d e d r e s u l t s w h i c h a r e o n l y p a r t i a l l y c o m p a t i b l e . The f o l l o w i n g s e c t i o n d i s c u s s e s p o s s i b l e e x p l a n a t i o n s f o r t h e o b s e r v e d d i s c r e p a n c i e s . 3 . D i s c u s s i o n o f t h e Modu lus R e s u l t s The l a r g e r a n g e o f modu lus v a l u e s r e p o r t e d by t h e l a b o r a t o r y t e s t i n g i s assumed t o r e f l e c t t h e h e t e r o g e n e o u s n a t u r e o f t h e r o c k t y p e s a t t h e s c a l e o f c o r e s p e c i m e n s . T h i s i s p o i n t e d l y d e m o n s t r a t e d by t h e q u a r t z f e l d s p a r s c h i s t i n w h i c h t h e modulus i s h i g h l y d e p e n d e n t on f o l i a t i o n o r i e n t a t i o n . F a u l t y i n s t r u m e n t a t i o n c o u l d c o n t r i b u t e t o a l a r g e r a n g e o f v a l u e s b u t i s n o t c o n s i d e r e d s i g n i f i c a n t i n t h e s e r e s u l t s i n v i e w o f t h e f r e q u e n t c a l i b r a t i o n c h e c k s . Compared t o t h e o t h e r t e s t i n g t e c h n i q u e s t h e mean v a l u e s f o r t h e l a b o r a t o r y t e s t s a r e s i g n i f i c a n t l y g r e a t e r . T h e s e r e s u l t s t h u s e s t a b l i s h t h e modulus o f t h e i n t a c t r o c k m a t e r i a l o r i n o t h e r words t h e u p p e r l i m i t f o r t h e modulus o f a j o i n t - r o c k mass s y s t e m . Compared t o e i t h e r o f t h e o t h e r t e s t i n g m e t h o d s , t h e Goodman J a c k r e s u l t s i n d i c a t e d t h r e e r o c k t y p e s o f l o w e r and more c o n s i s t e n t m o d u l u s . S e v e r a l p o s s i b l e e x p l a n a t i o n s c a n be c o n j e c t u r e d . On t h e a s s u m p t i o n t h a t t h e p l a t e l o a d i n g r e s u l t s f o r g n e i s s a r e a n o m o l o u s l y h i g h t h e n t h e Goodman J a c k r e s u l t s c o u l d be r e f l e c t i n g t h e t r u e in situ modulus o f t h e r o c k m a s s . T h i s e x p l a n a t i o n a l s o makes t h e a s s u m p t i o n t h a t s t r u c t u r a l f e a t u r e s c o n t r o l e q u a l l y t h e modulus o f a l l r o c k t y p e s . 112 In v i e w o f t h e d i s t i n c t d i f f e r e n c e i n f o l i a t i o n between g n e i s s and s c h i s t t h i s e x p l a n a t i o n i s u n l i k e l y . A s e c o n d e x p l a n a t i o n i s b a s e d on r e c e n t f i n i t e e l e m e n t m o d e l i n g o f t h e Goodman J a c k c a r r i e d o u t by Heuze and Dessenne [ 1 8 ] . In t h i s work t h e e f f e c t o f j o i n t s p a c i n g and in situ s t r e s s e s upon t h e measured d e f o r m a t i o n modulus was s t u d i e d . T h e i r method c a n be b r i e f l y d e s c r i b e d as f o l l o w s . F o r e a c h r o c k m a s s - j o i n t s y s t e m t h e t r u e modu lus c o u l d be d e t e r m i n e d f r o m t h e a s s i g n e d r o c k and j o i n t p r o p e r t i e s . S e v e r a l p o s s i b l e modes o f j a c k - b o r e h o l e i n t e r a c t i o n were s t u d i e d . The r e s u l t s were e x p r e s s e d i n t h e f o r m s o f s t r e s s p a t t e r n s a r o u n d t h e b o r e h o l e , e x t e n t o f r o c k b r e a k a g e a r o u n d and u n d e r t h e j a c k p l a t e s and t h e a p p a r e n t modulus o f d e f o r m a t i o n m e a s u r e d . T h i s a p p a r e n t modulus c o u l d be c o r r e c t e d t o t h e t r u e modu lus o f t h e r o c k - j o i n t s y s t e m by a d j u s t i n g t h e K v a l u e , ( s e e e q u a t i o n 1) The r e s u l t s showed t h a t f o r an u n j o i n t e d , i s o t r o p i c medium w h i c h e x h i b i t e d e l a s t i c b e h a v i o u r t h e K v a l u e i s 1 . 2 5 . T h i s i s t h e e x a c t v a l u e p r e d i c t e d by e l a s t i c t h e o r y and i n c i d e n t a l l y i s t h e v a l u e used f o r a l l c o m p u t a t i o n s i n t h i s t h e s i s . The r a n g e o f a d j u s t e d K v a l u e s was f r o m 0 . 7 5 t o 3 . 1 3 d e p e n d i n g on t h e p r e s e n c e o f j o i n t s and in situ s t r e s s e s . The i n v e s t i g a t o r s c o n c l u d e d t h a t \" t h e r e e x i s t c r i t i c a l j o i n t s p a c i n g s w h i c h by a l l o w i n g i m p o r t a n t r o c k b r e a k a g e , i n t r o d u c e s i g n i f i c a n t e r r o r s i n t e s t r e s u l t s u n l e s s t h e r o c k y i e l d i n g i s a c c o u n t e d f o r . \" They a l s o a d v i s e d t h a t f o r a c o m p l e t e a n a l y s i s o f t e s t r e s u l t s a d d i t i o n a l i n f o r m a t i o n c o n s i s t i n g o f t h e s t r e n g t h o f t h e s u b s t a n c e , t h e s p a c i n g o f f r a c t u r e s and t h e in situ s t r e s s e s i s n e c e s s a r y . They a l s o m e n t i o n e d a d d i t i o n a l f a c t o r s s u c h as d i l a t a n c y o f t h e j o i n t s and d e g r e e o f r o c k a n i s o t r o p y w h i c h may i n f l u e n c e Goodman J a c k t e s t s b u t w h i c h t o d a t e have n o t been i n v e s t i g a t e d . 113 In v i e w o f t h e r e c e n t work by Heuze and Dessenne t h e r e s u l t s o f t h e Goodman J a c k t e s t i n g i n T a b l e 3 c o u l d be m o d i f i e d f r o m -40% t o + 165% d e p e n d i n g on t h e a p p l i c a b l e K f a c t o r a t e a c h t e s t l o c a t i o n . T h i s l a r g e r a n g e o f c o r r e c t i o n c o u l d e a s i l y a c c o u n t f o r t h e l o w r a n g e and l o w v a l u e s o f Goodman J a c k modulus r e s u l t s . The p l a t e l o a d r e s u l t s a r e s u r p r i s i n g i n v i e w o f t h e l a r g e modulus f o r t h e g n e i s s compared t o t h a t o b t a i n e d f r o m t h e Goodman J a c k . T h i s anomaly c o u l d r e s u l t f r o m d i s c r e p a n c i e s i n t h e Goodman J a c k ( i . e . v a r i a t i o n o f t h e K f a c t o r ) o r f r o m p l a t e l o a d t e s t s i n t h e f o l l o w i n g manner . The p l a t e l o a d i n g t e s t s a r e i n t e r p r e t a t e d u s i n g f o r m u l a e d e v e l o p e d f r o m e l a s t i c i t y t h e o r y . T h i s a p p l i c a t i o n i s d u b i o u s i n v i e w o f t h e r o c k q u a l i t y s u r r o u n d i n g t h e t u n n e l . I t w o u l d t h u s be a d v i s a b l e t o c a r r y o u t a f i n i t e e l e m e n t s t u d y f o r t h e p l a t e l o a d i n g t e s t s i m i l a r t o t h a t c a r r i e d o u t f o r t h e Goodman J a c k by Heuze and Dessenne [ 1 8 ] . A s e c o n d though l e s s s i g n i f i c a n t f a c t o r i s t h e a c c u r a c y o f t h e d e f o r m a t i o n s e n s i n g s y s t e m . T h i s i s i n d i c a t e d by t h e l a c k o f d e f o r m a t i o n r e s p o n s e when c h a n g i n g f r o m l o a d i n g t o u n l o a d i n g and i s r e f l e c t e d by v e r y s t e e p u n l o a d c u r v e s , ( s e e F i g u r e s 47 and 48) A l a c k o f d e f o r m a t i o n s e n s i t i v i t y c a n i n c r e a s e t h e a p p a r e n t r o c k modulus and i s more p r o n o u n c e d f o r h i g h e r modulus r o c k s . In summary , the r e s u l t s d i s c u s s e d above i n d i c a t e t h a t modulus v a l u e s f r o m d i f f e r e n t t e s t i n g t e c h n i q u e s c a n n o t be r e a l i s t i c a l l y compared w i t h o u t d e t a i l e d knowledge o f e a c h t e s t e n v i r o n m e n t and w i t h o u t v a l i d i n t e r p r e t a t i o n f o r m u l a e . In o t h e r w o r d s , t h e l a c k o f c o r r e l a t i o n between t h e t h r e e t e s t i n g programmes r e f l e c t s t h e need t o c o n v e n i e n t l y q u a n t i f y i m p o r t a n t f a c t o r s s u c h as r o c k q u a l i t y and in situ s t r e s s e s and t o i n c o r p o r a t e t h e s e f a c t o r s i n t o v a l i d i n t e r p r e t i v e f o r m u l a e . T h i s t o p i c w i l l be expanded i n S e c t i o n V I L E , on t h e p r a c t i c a l a p p l i c a t i o n o f t h e s e r e s u l t s . B. A n i s o t r o p y A n i s o t r o p y r e s u l t s f o r t h e l a b o r a t o r y and p l a t e l o a d i n g t e s t s a r e f a i r l y c o n s i s t e n t . The l a b o r a t o r y t e s t i n g shows i n c o n c l u s i v e a n i s o t r o p y f o r t h e g n e i s s and e x c e l l e n t a n i s o t r o p y f o r t h e s c h i s t . The i n d i c a t e d r a t i o o f m o d u l i f o r l o a d i n g p a r a l l e l and p e r p e n d i c u l a r t o t h e f o l i a t i o n i s a b o u t 2 . 5 f o r t h e s c h i s t . The p l a t e l o a d i n g t e s t s i n d i c a t e t h e g n e i s s i s 2.4 t i m e s as r i g i d when l o a d e d p a r a l l e l t o t h e l a y e r i n g t h a n when l o a d e d p e r p e n d i c u l a r . The r e s u l t f o r t h e s c h i s t i s 2 . 2 t i m e s . A n i s o t r o p y i n v e s t i g a t i o n s on t h e Goodman J a c k r e s u l t s a r e i n c o n c l u s i v e . A l t h o u g h t h e j a c k i n d i c a t e s a n i s o t r o p i c b e h a v i o u r f o r t h e s c h i s t , q u a n t i t a t i v e a n a l y s i s i s i m p o s s i b l e w i t h o u t a c c u r a t e g e o l o g i c c o n t r o l a t t h e t e s t l o c a t i o n s . Thus a n i s o t r o p y c a n o n l y be i n v e s t i g a t e d w i t h t h e j a c k u n d e r v e r y u n i f o r m g e o l o g i c c o n d i t i o n s o r where a s u p p l e m e n t a r y programme o f o r i e n t e d c o r e d r i l l i n g o r bo re h o l e camera l o g g i n g i s e m p l o y e d . C. E l a s t i c R e c o v e r y The e l a s t i c r e c o v e r i e s i n d i c a t e d by t h e t h r e e programmes show an i n t e r e s t i n g t r e n d . F o r e a s y c o m p a r i s o n t h e a v e r a g e e l a s t i c r e c o v e r i e s f o r c o m p l e t e t e s t s a r e s u m m a r i z e d : 115 L a b o r a t o r y t e s t i n g : g n e i s s : 93% p e g m a t i t e : 89% s c h i s t : 84% Goodman J a c k t e s t i n g : g n e i s s : 60% p e g m a t i t e : 56% s c h i s t : 59% P l a t e l o a d i n g t e s t s : g n e i s s : 30% s c h i s t : 29% The o b v i o u s t r e n d i s t h a t e l a s t i c r e c o v e r y d e c r e a s e d w i t h i n c r e a s i n g vo lume o f r o c k t e s t e d . T h i s i s t o be e x p e c t e d s i n c e t h e l a r g e r volume t e s t s i n c o r p o r a t e a g r e a t e r number o f g e o l o g i c d i s c o n t i n u i t i e s . F o r t h e l a b o r a t o r y and Goodman J a c k t e s t s t h e d e f o r m a t i o n i s e s s e n t i a l l y e l a s t i c a f t e r t h e f i r s t l o a d i n g c y c l e . The p l a t e l o a d i n g t e s t s , on t h e o t h e r h a n d , showed an a v e r a g e o f 30% permanent d e f o r m a t i o n on t h e f i n a l l o a d i n g c y c l e . The d i s c r e p a n c y i s p r o b a b l y due t o t h e l a r g e r vo lume o f r o c k a f f e c t e d by t h e p l a t e l o a d i n g t e s t as w e l l as t h e zone o f m i c r o -f r a c t u r e d and d e - s t r e s s e d r o c k a r o u n d t h e d r i f t . D. Ease o f P e r f o r m a n c e A f i n a l c o m p a r i s o n , b a s e d on t h e t i m e r e q u i r e d t o o b t a i n l o a d -d e f o r m a t i o n d a t a , c a n be made between t e s t i n g t e c h n i q u e s . The t i m e r e q u i r e d t o r e d u c e t h e d a t a t o modulus v a l u e s i s n o t i n c l u d e d s i n c e i t i s e q u a l f o r a l l m e t h o d s . F o r t h e l a b o r a t o r y s a m p l e s , i n c l u d i n g sample p r e p a r a t i o n and t e s t i n g , t h e t o t a l t i m e i s 1 3 / 4 h o u r s p e r two c y c l e 116 t e s t . The t i m e r e q u i r e d f o r a two c y c l e t e s t w i t h t h e Goodman J a c k i s f r o m 10 t o 20 m i n u t e s d e p e n d i n g on t h e t i m e n e c e s s a r y t o p o s i t i o n t h e j a c k a t t h e t e s t l o c a t i o n . T h i s t i m e assumes t h a t b o r e h o l e s a r e r e q u i r e d f o r an e a r l i e r e x p l o r a t i o n p h a s e o f t h e p r o j e c t . The company p e r f o r m -i n g t h e p l a t e l o a d i n g t e s t s r e p o r t s t h a t a f o u r c y c l e t e s t r e q u i r e d 6 t o 8 h o u r s e x c l u s i v e o f p r e p a r a t i o n t i m e . O b v i o u s l y t h i s l a t t e r t e s t i s t h e most t i m e c o n s u m i n g and hence most e x p e n s i v e t o p e r f o r m . E. E v a l u a t i o n o f T e s t i n g T e c h n i q u e s In v i e w o f t h e i n c o n s i s t e n c i e s p r o v i d e d by t h e c o m p a r i s o n o f t h e t h r e e t e s t i n g t e c h n i q u e s some o b s e r v a t i o n s on t h e p r a c t i c a l v a l u e o f t h e r e s u l t s as w e l l as p o s s i b l e improvements t o t h e t e c h n i q u e s w o u l d be r e l e v e n t . B e f o r e p e r f o r m i n g a t e s t t o d e t e r m i n e a p h y s i c a l r o c k p r o p e r t y s u c h as d e f o r m a t i o n m o d u l u s , t h e r e q u i r e d a c c u r a c y o f t h e p r o p e r t y s h o u l d be e v a l u a t e d . F o r e x a m p l e , t o d e l i n e a t e z o n e s o f s i g n i f i c a n t l y d i f f e r e n t d e f o r m a t i o n modulus t h e r e q u i r e d a c c u r a c y o f t h e modulus may be ± 100%. On t h e o t h e r h a n d , t h e d e f o r m a t i o n modulus o f t h e r o c k s u r r o u n d i n g a p r e s s u r e c o n d u i t may haye t o be known w i t h i n 25%. O b v i o u s l y t h e s o p h i s t i c a t i o n o f t h e t e s t i n g t e c h n i q u e r e q u i r e d i n t h e s e two c a s e s w o u l d be q u i t e d i f f e r e n t . F o l l o w i n g t h i s r e a s o n i n g i t i s c o n v e n i e n t t o d i s t i n g u i s h t e s t s as r e p o r t i n g e i t h e r i n d e x v a l u e s o r d e s i g n v a l u e s . An i n d e x v a l u e i s one w h i c h i s p r o p o r t i o n a l t o t h e t r u e v a l u e and t h u s w i l l r e f l e c t t r e n d s . A d e s i g n v a l u e v e r y n e a r l y r e f l e c t s t h e t r u e b e h a v i o u r o f t h e t e s t e d medium. C o n s i d e r t h e d e f o r m a t i o n b e h a v i o u r o f a j o i n t - r o c k mass s y s t e m as t h e p r o p e r t y w h i c h must be d e t e r m i n e d . Each o f t h e t h r e e 117 t e s t i n g t e c h n i q u e s i n t h i s t h e s i s c a n be e v a l u a t e d a c c o r d i n g t o t h e d e s i g n v a l u e v e r s u s i n d e x v a l u e c r i t e r i a . 1 . L a b o r a t o r y T e s t i n g S i n c e t h e r o c k d i s c o n t i n u i t i e s a r e l o s t i n t h e s a m p l i n g p r o c e s s l a b o r a t o r y t e s t i n g p r o v i d e s o n l y an i n d e x t o t h e d e f o r m a t i o n b e h a v i o u r o f a j o i n t - r o c k mass s y s t e m . The t e s t i s v a l u a b l e i n t h a t i t c o n v e n i e n t l y d e t e r m i n e s an u p p e r bound t o t h e d e f o r m a t i o n modu lus o f a r o c k mass a s was shown i n F i g u r e 5 0 . A t t e m p t s have been made t o i m p r o v e t h e v a l u e o f l a b o r a t o r y t e s t i n g as an i n d e x t e s t by c o r r e l a t i n g t h e modu lus o f t h e r o c k s a m p l e w i t h i n d i c e s r e l a t e d t o t h e q u a l i t y o f t h e r o c k m a s s . S e v e r a l i n d i c e s f o r r o c k q u a l i t y have been p r o p o s e d : 1 . The f r a c t u r e f r e q u e n c y . 2 . The Rock Q u a l i t y D e s i g n a t i o n o r RQD. The RQD i s d e f i n e d as t h e p e r c e n t o f t h e c o r i n g i n t e r v a l r e p r e s e n t e d i n t h e c o r e box by s o u n d , u n w e a t h e r e d c y l i n d e r s a t l e a s t f o u r i n c h e s i n l e n g t h . [ S t a g g and Z i e n k i e w i c z , 2 ] 3 . The r a t i o o f t h e in situ c o m p r e s s i o n a l wave v e l o c i t y t o t h a t o b t a i n e d f r o m l a b o r a t o r y s p e c i m e n s . I n v e s t i g a t i o n s i n t o t h e p o s s i b i l i t y o f c o r r e l a t i n g d e f o r m a t i o n modu lus w i t h r o c k q u a l i t y i n d i c e s have been c a r r i e d o u t by D e e r e , H e n d r o n , e t a l _ . [ 1 9 ] , Onodera [ 2 0 ] , and Coon and M e r r i t t [ 2 1 ] . A l t h o u g h a p p r o x i m a t e r e l a t i o n s h i p s have been d e f i n e d i t i s u n l i k e l y t h a t a r e l i a b l e method w i l l be f o u n d t o r e d u c e t h e modu lus o f a l a b o r a t o r y s a m p l e t o t h a t o f a j o i n t - r o c k mass s y s t e m u s i n g r o c k q u a l i t y i n d i c e s . The r e a s o n b e i n g t h a t 118 t h e s e i n d i c e s r e f l e c t t h e p o p u l a t i o n o f t h e r o c k d i s c o n t i n u i t i e s b u t n o t t h e i r d e f o r m a t i o n b e h a v i o u r . F i n i t e e l e m e n t m o d e l l i n g o f a j o i n t - r o c k mass s y s t e m c a n i n c o r -p o r a t e t h e d e f o r m a t i o n p r o p e r t i e s o f t h e r o c k s u b s t a n c e and j o i n t s s e p a r a t e l y . I t i s t h e r e f o r e c o n c e i v a b l e t h a t l a b o r a t o r y t e s t i n g c o u l d p r o v i d e d a t a f o r t h e d e t e r m i n a t i o n o f d e s i g n modulus v a l u e s f o r a j o i n t -r o c k mass s y s t e m . A t p r e s e n t t h e r e a r e two o b s t a c l e s t o t h i s p r o c e d u r e : 1 . A c o n v e n i e n t s a m p l i n g t e c h n i q u e f o r o b t a i n i n g r o c k samp les i n c l u d i n g j o i n t s i s n e e d e d . [ B u k o v a n s k y , 3 ] 2 . A s i m p l e method o f d e t e r m i n i n g j o i n t d e f o r m a t i o n p r o p e r t i e s i s r e q u i r e d . [ B u k o v a n s k y , 3 ] I n summary, l a b o r a t o r y t e s t i n g p r o v i d e s an i n d e x t o t h e d e f o r -m a t i o n p r o p e r t i e s o f a j o i n t - r o c k mass s y s t e m . T h i s i n d e x c a n be i m p r o v e d by c o r r e l a t i o n w i t h r o c k q u a l i t y i n d i c e s . In t h e f u t u r e , l a b o r a t o r y t e s t i n g c o u p l e d w i t h f i n i t e e l e m e n t a n a l y s i s may p r o v i d e d e s i g n modulus v a l u e s . 2 . Goodman J a c k T e s t i n g The r e s u l t s i n t h i s t h e s i s i l l u s t r a t e two ma in p o i n t s o f t h e Goodman J a c k t e s t i n g t e c h n i q u e : 1 . The j a c k p r o v i d e s an e x t r e m e l y e f f i c i e n t method f o r o b t a i n i n g a l a r g e amount o f l o a d - d e f o r m a t i o n d a t a f o r an e x t e n s i v e number o f in situ t e s t l o c a t i o n s . 119 2 . The l a c k o f r o c k t y p e d i f f e r e n t i a t i o n based on modulus p r o b a b l y r e f l e c t s t h e need t o u t i l i z e a p p r o p r i a t e K v a l u e s i n t h e i n t e r p r e t i v e f o r m u l a . The s u p p l e m e n t a r y t e s t i n g programmes n e c e s s a r y t o d e t e r m i n e t h e a p p r o p r i a t e K v a l u e f o r e a c h t e s t l o c a t i o n w o u l d o f f s e t t h e e f f i c i e n c y o f t h e method . Two a l t e r n a t i v e Goodman J a c k t e c h n i q u e s t o p r o v i d e i n d e x modulus v a l u e s f o l l o w f r o m t h i s . F i r s t l y , t h e t e s t i n g can be c a r r i e d o u t as f o r t h i s t h e s i s w i t h no s u p p l e m e n t a r y programmes and t h e r e s u l t s i n t e r p r e t e d u s i n g t h e K v a l u e f o r an e l a s t i c medium o r a l t e r n a t i v e l y , a v a l u e a p p r o p r i a t e f o r an \" a v e r a g e \" r o c k m a s s . As s u c h t h e t e s t w o u l d p r o v i d e a r o u g h i n d e x t o t h e modulus o f a j o i n t - r o c k mass s y s t e m . In t h e a u t h o r ' s o p i n i o n a s e c o n d more d e s i r a b l e method c o u l d be d e v i s e d as f o l l o w s : 1 . F u r t h e r f i n i t e e l e m e n t m o d e l l i n g o f t h e j a c k as recommended by Heuze and Dessenne [ 1 8 ] s h o u l d be c a r r i e d o u t t o i n v e s t i g a t e a l l r o c k p a r a m e t e r s w h i c h can a f f e c t t h e K v a l u e . 2 . Knowing t h e r e l e v e n t p a r a m e t e r s t h e K v a l u e c o u l d be c o r r e l a t e d w i t h one o r more s i m p l e r o c k q u a l i t y i n d i c e s . These i n d i c e s s h o u l d be o b t a i n e d f r o m t h e NX c o r e c o r r e s p o n d i n g t o t h e Goodman J a c k t e s t l o c a t i o n . S u i t a b l e r o c k q u a l i t y i n d i c e s f o r c o r r e l a t i o n w o u l d be RQD and P o i n t Load S t r e n g t h . F o r an e x t e n s i v e d e s c r i p t i o n o f t h e P o i n t Load S t r e n g t h T e s t s e e B r o c h and F r a n k l i n [ 2 2 ] . 3 . The a p p r o p r i a t e K v a l u e f o r e a c h Goodman J a c k t e s t l o c a t i o n w o u l d be d e r i v e d f r o m c o r r e l a t i o n s between K and t h e v a r i o u s r o c k i n d i c e s . The p r o p o s e d t e s t p r o c e d u r e w o u l d r e q u i r e t h e o r e t i c a l v e r i f i c a t i o n as w e l l as e x t e n s i v e f i e l d e v a l u a t i o n and i f s u c c e s s f u l s h o u l d i m p r o v e t h e i n d e x modulus v a l u e s r e p o r t e d by t h e Goodman J a c k . R e c e n t f i n i t e e l e m e n t i n v e s t i g a t i o n s by Heuze and Dessenne [ 1 8 ] i n d i c a t e t h a t i n c l o s e l y j o i n t e d r o c k t h e j a c k c o u l d a l s o p r o v i d e d e s i g n modulus v a l u e s . T h i s a p p l i c a t i o n o f t h e j a c k w o u l d r e q u i r e f u r t h e r t h e o r e t i c a l i n v e s t i g a t i o n as w e l l a s c o n s i d e r a t i o n t o p r a c t i c a l ways o f d e t e r m i n i n g t h e a d d i t i o n a l t e s t d a t a , i n c l u d i n g in situ s t r e s s , j o i n t s p a c i n g , r o c k s t r e n g t h and p e r h a p s a d d i t i o n a l f a c t o r s . In o r d e r t o f u r t h e r v a l i d a t e t h e d e s i g n v a l u e s r e p o r t e d by t h e j a c k and i n v i e w o f t h e l e s s t h a n a d e q u a t e t e s t s r e p o r t e d by T r a n [ 7 ] and by H e u z e , e t a l . [ 2 3 ] , t h i s a u t h o r w o u l d recommend a t h o r o u g h l a b o r a t o r y s t u d y t o c o n f i r m t h e t h e o r e t i c a l i n v e s t i g a t i o n s . T h i s programme w o u l d u t i l i z e a l a r g e homogeneous, n o n - c o m p o s i t e b l o c k o f r o c k . T e s t s c a r r i e d o u t i n NX b o r e h o l e s i n t h e b l o c k w o u l d be compared t o u n i a x i a l o r t r i a x i a l d e f o r m a t i o n t e s t s c a r r i e d o u t on l a r g e vo lume c o r e s a m p l e s f r o m t h e same r o c k b l o c k . By u t i l i z i n g s p e c i a l d r i l l b i t s t h e e f f e c t s o f b o r e h o l e r o u g h n e s s and e c c e n t r i c i t y c o u l d be s t u d i e d . W i t h s p e c i a l i z e d e q u i p m e n t e x t e r n a l l o a d s c o u l d be a p p l i e d t o t h e r o c k b l o c k t o i n v e s t i g a t e t h e dependence o f modulus on t h e l o a d i n g d i r e c t i o n - s t r e s s r e l a t i o n s h i p . O b v i o u s l y n o t a l l t h e in situ p a r a m e t e r s c o u l d be d u p l i c a t e d i n t h e l a b o r a t o r y b u t t h e a b i l i t y t o v a r y s e l e c t e d p a r a m e t e r s s h o u l d p r o v i d e v a l u a b l e i n f o r m a t i o n . 121 In summary, t h e r e s u l t s o f t h i s t h e s i s have i n d i c a t e d t h a t t h e Goodman J a c k p r o v i d e s an e x c e l l e n t method o f d e t e r m i n i n g an i n d e x t o t h e in situ d e f o r m a t i o n b e h a v i o u r o f a j o i n t - r o c k mass s y s t e m . W i t h f u r t h e r r e s e a r c h t h e j a c k s h o u l d p r o v i d e i m p r o v e d i n d e x modulus v a l u e s and p o s s i b l y d e s i g n modulus v a l u e s u n d e r s p e c i f i c s i t e c o n d i t i o n s . 3. P l a t e L o a d i n g T e s t s The p l a t e l o a d i n g t e s t s as c a r r i e d o u t f o r t h i s t h e s i s a r e c o n s i d e r e d an i n d e x t e s t . T h i s i s b a s e d on t h e f a c t t h a t a l e s s t h a n i d e a l d e f o r m a t i o n m e a s u r i n g s y s t e m was u t i l i z e d and b e c a u s e t h e a p p l i c a t i o n o f e l a s t i c i t y t h e o r y t o t h e zone o f b l a s t damaged, and d e s t r e s s e d r o c k s u r r o u n d i n g t h e d r i f t i s u n r e l i a b l e . In t h e a u t h o r ' s o p i n i o n p l a t e l o a d i n g t e s t s s h o u l d be u t i l i z e d t o p r o v i d e d e s i g n v a l u e s r a t h e r t h a n i n d e x modulus v a l u e s . The r e a s o n b e i n g t h a t t h e u t i l i z a -t i o n o f e x p e n s i v e and cumbersome p l a t e l o a d i n g t e s t s t o p r o v i d e i n d e x modulus v a l u e s i s n o t e c o n o m i c a l l y j u s t i f i e d when compared t o r a p i d , i n e x p e n s i v e methods s u c h as t h e Goodman J a c k . In o r d e r t o o b t a i n d e s i g n modulus v a l u e s f r o m t h e p l a t e l o a d i n g t e s t s a d d i t i o n a l c o s t s w o u l d be i n c u r r e d , however t h e a d d i t i o n a l e x p e n s e w o u l d be w a r r a n t e d when compared t o t h e t o t a l c o s t o f t h e method . The f o l l o w i n g a d d i t i o n a l r e q u i r e m e n t s w o u l d have t o be met : 1 . The l i n e a r d i m e n s i o n o f t h e l o a d e d a r e a s h o u l d be l a r g e compared t o t h e s p a c i n g o f d i s c o n t i n u i t i e s i n t h e r o c k . [ S t a g g and Z i e n k i e w i c z , 2 ] 122 2 . The s t r e s s l e v e l s c r e a t e d by t h e t e s t s h o u l d be c o m p a r a b l e t o t h o s e g e n e r a t e d by t h e p r o t o t y p e l o a d i n g . The c o m p l i a n c e o f t h e p l a t e l o a d t e s t s t o p o i n t s 1 and 2 o b v i o u s l y r e s t r i c t s t h e s t r u c t u r a l g e o l o g i c e n v i r o n m e n t s i n w h i c h p l a t e l o a d i n g t e s t s c a n be u t i l i z e d t o p r o v i d e d e s i g n modulus v a l u e s . 3 . B o r e h o l e s s h o u l d be d r i l l e d u n d e r t h e b e a r i n g pads a t e a c h t e s t l o c a t i o n f o r two r e a s o n s . F i r s t l y , l o g g i n g t h e c o r e o f t h e b o r e h o l e s w o u l d p r o v i d e d e t a i l e d s t r u c t u r a l g e o l o g y b e n e a t h t h e b e a r i n g p a d s . S e c o n d l y , t h e h o l e s c o u l d be i n s t r u m e n t e d w i t h m u l t i p l e p o s i t i o n b o r e h o l e e x t e n s o m e t e r s i n o r d e r t o r e l a t e d e f o r m a t i o n t o g e o l o g i c s t r u c t u r e . ( F o r a d e s c r i p t i o n o f s u c h a s y s t e m see B e n s o n , e t a l . , 1 4 ] . 4 . As a c h e c k on t h e t o t a l d e f o r m a t i o n t h e d i s t a n c e between t h e b e a r i n g pads s h o u l d be m o n i t o r e d u s i n g a r o d t y p e e x t e n s o m e t e r . 5 . A f i n i t e e l e m e n t model s h o u l d be used t o i n v e s t i g a t e t h e e f f e c t s o f j o i n t s p a c i n g , in situ s t r e s s e s and r o c k s t r e n g t h and t h u s p r o v i d e a v a l i d i n t e r p r e t i v e f o r m u l a f o r p l a t e l o a d i n g t e s t s . In summary, t h e p e r f o r m i n g o f p l a t e l o a d t e s t s t o p r o v i d e i n d e x modulus v a l u e s i s c o n s i d e r e d u n w a r r a n t e d i n v i e w o f t h e p o t e n t i a l o f d e s i g n v a l u e s a t s l i g h t a d d i t i o n a l e x p e n s e . 123 CHAPTER V I I I CONCLUSION The r e s u l t s o f t h e t h r e e t e s t i n g programmes a r e s u b d i v i d e d i n t o t h r e e g r o u p i n g s i n o r d e r t o r e a c h c o n c l u s i o n s ; a n i s o t r o p y , e l a s t i c b e h a v i o u r and d e f o r m a t i o n m o d u l u s . Q u a n t i t a t i v e a n i s o t r o p y r e s u l t s were p r o v i d e d by t h e l a b o r a t o r y and p l a t e l o a d i n g t e s t s . A l t h o u g h t h e s c a l e o f t h e s e t e s t s i s q u i t e d i f f e r e n t t h e d e g r e e o f a n i s o t r o p y was c o m p a r a b l e f o r b o t h m e t h o d s . The Goodman J a c k p r o v i d e d o n l y an i n d i c a t i o n o f a n i s o t r o p i c r o c k b e h a v i o u r . I t i s c o n c l u d e d t h a t e a c h o f t h e t e s t i n g methods have i n h e r e n t l i m i t a t i o n s f o r i n v e s t i g a t i n g t h e dependence o f modulus on l o a d i n g d i r e c t i o n . L a b o r a t o r y t e s t s p r o v i d e e x c e l l e n t d i r e c t i o n a l p r o p e r t i e s o f t h e r o c k s u b s t a n c e b u t have l i m i t e d a p p l i c a t i o n t o t h e a n i s o t r o p y o f a j o i n t -r o c k mass s y s t e m . P l a t e l o a d i n g t e s t s a r e r e s t r i c t e d i n t h a t a n i s o t r o p y r e s u l t s c a n be m o d i f i e d by t h e d r i f t e x c a v a t i o n p r o c e s s as w e l l as by t h e b e a r i n g pad p r e p a r a t i o n . Goodman J a c k t e s t s s u f f e r f r o m t h e f a c t t h a t v e r y d e t a i l e d b o r e h o l e d a t a i s r e q u i r e d i n o r d e r t o o b t a i n q u a n t i t a t i v e a n i s o t r o p y r e s u l t s . The e l a s t i c b e h a v i o u r o f t h e r o c k as r e f l e c t e d by t h e t h r e e t e s t i n g methods i l l u s t r a t e d t h e s c a l e e f f e c t . The e l a s t i c r e c o v e r y f o r a c o m p l e t e t e s t l o a d i n g was d i r e c t l y p r o p o r t i o n a l t o t h e r o c k vo lume i n f l u e n c e d by t h e t e s t method . A l s o , s i n c e an u n j o i n t e d r o c k mass behave much more e l a s t i c a l l y t h a n a j o i n t - r o c k mass s y s t e m t h e e l a s t i c r e c o v e r i e s a l s o r e f l e c t t h e r o c k q u a l i t y o f t h e t e s t e n v i r o n m e n t . 124 From t h e c o m p a r i s o n o f modulus v a l u e s r e p o r t e d by t h e t h r e e t e s t i n g methods i t was shown t h a t t h e r e s u l t s d e v i a t e d f r o m and c o n -fo rmed t o t h e e x p e c t e d r e s u l t s . In e x p l a n a t i o n , s e v e r a l p o s s i b l e e x t e r n a l f a c t o r s s u c h a s j o i n t s p a c i n g , in situ s t r e s s and v a l i d i t y o f t h e i n t e r p r e t i v e f o r m u l a were p r e s e n t e d . I t i s t h e r e f o r e c o n c l u d e d t h a t w i t h o u t d e f i n i n g , q u a n t i f y i n g and i n c o r p o r a t i n g t h e i m p o r t a n t t e s t v a r i a b l e s , a c o m p a r i s o n between t e s t i n g t e c h n i q u e s c a n o n l y be made i n g e n e r a l i z e d t e r m s . The i n d e x v a l u e v e r s u s d e s i g n v a l u e c l a s s i f i -c a t i o n i s an example o f a g e n e r a l i z e d c o m p a r i s o n . In summary, t h e Goodman J a c k t e s t s p r o v i d e e x c e l l e n t i n d e x modulus v a l u e s f o r a j o i n t - r o c k mass s y s t e m , l a b o r a t o r y t e s t s , t hough c o n v e n i e n t t o p e r f o r m , y i e l d i n d e x v a l u e s o f r e s t r i c t e d a p p l i c a t i o n and p l a t e l o a d i n g t e s t s a r e most e c o n o m i c a l l y u t i l i z e d as d e s i g n v a l u e t e s t s . 125 B I B L I O G R A P H Y BIBLIOGRAPHY KRUSE, G . H . , D e f o r m a b i l i t y o f Rock S t r u c t u r e s , C a l i f o r n i a S t a t e Water P r o j e c t , D e t e r m i n a t i o n o f t h e In Situ Modu lus o f D e f o r m a t i o n o f R o c k , ASTM STP 4 7 7 , Am. S o c . T e s t i n g \" M a t s . , 1 9 7 0 . STAGG, K . G . and Z IENKIEWICZ , O . C . , Rock M e c h a n i c s i n E n g i n e e r i n g P r a c t i c e , J o h n W i l e y and S o n s , New Y o r k , 1 9 6 8 . BUKOVANSKY, M . , D e t e r m i n a t i o n o f E l a s t i c P r o p e r t i e s o f Rocks U s i n g V a r i o u s O n - S i t e and L a b o r a t o r y M e t h o d s , P r o c e e d i n g s o f t h e Second C o n g r e s s o f t h e I n t e r n a t i o n a l S o c i e t y f o r Rock M e c h a n i c s 1 , B e l g r a d e , Y u g o s l a v i a , 1970 . DALLY, J . W . and R I L E Y , W . F . , E x p e r i m e n t a l S t r e s s A n a l y s i s , M c G r a w H i l l Book C o . , 1 9 6 5 . HARDY, H . R . , S t a n d a r d i z e d P r o c e d u r e s f o r t h e D e t e r m i n a t i o n o f t h e P h y s i c a l P r o p e r t i e s o f M ine Rock u n d e r S h o r t - P e r i o d U n i a x i a l C o m p r e s s i o n ; Depa r tment o f M i n e s and T e c h n i c a l S u r v e y s , O t t a w a , M i n e s B r a n c h T e c h n i c a l B u l l e t i n TB 8 , 1959 . CLARK, G . B . , D e f o r m a t i o n Modu lus o f R o c k s , T e s t i n g T e c h n i q u e s f o r Rock M e c h a n i c s , ASTM STP 4 0 2 , Am. S o c . T e s t i n g M a t s . , 1965 . TRAN, V . K . , In Situ D e t e r m i n a t i o n o f Rock D e f o r m a b i l i t y by B o r e h o l e J a c k T e s t s , u n p u b l i s h e d M . S c . T h e s i s , U n i v e r s i t y o f C a l i f o r n i a , B e r k e l e y , 1967 . Z IENKIEWICZ , O . C . and STAGG, K . G . , C a b l e Method o f In Situ Rock T e s t i n g , I n t e r n a t i o n a l J o u r n a l o f Rock M e c h a n i c s and M i n i n g S c i e n c e s 4 , 1967 . WALLACE, G . B . , S L E B I R , E . J . and ANDERSON, F . A . , In Situ Methods f o r D e t e r m i n i n g D e f o r m a t i o n Modu lus Used by t h e B u r e a u o f R e c l a m a t i o n , D e t e r m i n a t i o n o f t h e In Situ Modu lus o f D e f o r m a t i o n o f R o c k , ASTM STP 4 7 7 , Am. S o c . T e s t i n g M a t s . , 1 9 7 0 . OBERT, L . and DUVALL, W . I . , Rock M e c h a n i c s and t h e D e s i g n o f S t r u c t u r e s i n R o c k , J o h n W i l e y and S o n s , New Y o r k , 1 9 6 7 . 127 1 1 . HAWKES, I . and MELLOR, M . , U n i a x i a l T e s t i n g i n Rock M e c h a n i c s L a b o r a t o r i e s , E n g i n e e r i n g G e o l o g y , V o l . 4 , 1970 . 1 2 . GOODMAN, R . E . , TRAN, V . K . and HEUZE, F . E . , The Measurement o f Rock D e f o r m a b i l i t y i n B o r e H o l e s , P r o c e e d i n g s o f t h e T e n t h Symposium on Rock M e c h a n i c s , A I M E , 1 9 6 8 . 1 3 . ROARK, F . J . , F o r m u l a s f o r S t r e s s and S t r a i n , M c G r a w - H i l l Book Company, I n c . , 1954 . 14 . BENSON, R . P . , MURPHY, D . K . and McCREATH, D . R . , Modu lus T e s t i n g o f Rock a t t h e C h u r c h i l l F a l l s Underg round P o w e r h o u s e , L a b r a d o r , D e t e r m i n a t i o n o f t h e In Situ Modu lus o f D e f o r m a t i o n o f R o c k , ASTM STP 4 7 7 , Am. S o c . T e s t i n g M a t s . , 1970 . 1 5 . SMITHELLS, C . J . , M e t a l s R e f e r e n c e B o o k , I n t e r s c i e n c e P u b l i s h e r s , I n c . , New Y o r k , 1955 . 16 . HAWKES, I . , M o d u l i Measurements on Rock C o r e s , P r o c e e d i n g s o f t h e F i r s t C o n g r e s s o f t h e I n t e r n a t i o n a l S o c i e t y f o r Rock M e c h a n i c s , L i s b o n , 1966 . 17 . GUTTMAN, I . and WILKS, S . S . , I n t r o d u c t o r y E n g i n e e r i n g S t a t i s t i c s , J o h n W i l e y and S o n s , I n c . , 1965 . 18 . HEUZE, F . E . and DESSENNE, D . , The I n f l u e n c e o f J o i n t S p a c i n g , and t h e E f f e c t o f Rock B r e a k a g e , on B o r e h o l e D e f o r m a b i l i t y T e s t R e s u l t s , R e p o r t t o U . S . Army C o r p s o f E n g i n e e r s , Omaha, N e b r a s k a , 1972 . 1 9 . DEERE, D . U . , HENDRON, A . J . , J r . , PATTON, F . D . , and CORDING, E . J . , D e s i g n o f S u r f a c e and N e a r - s u r f a c e C o n s t r u c t i o n i n R o c k , P r o c . 8 t h Symposium on Rock M e c h . , A I M E , 1966 . 2 0 . ONODERA, T . F . , Dynamic I n v e s t i g a t i o n o f F o u n d a t i o n Rocks In Situ , P r o c e e d i n g s o f t h e F i f t h Symposium on Rock M e c h a n i c s , M i n n e s o t a , Pergamon P r e s s , 1 9 6 3 . 2 1 . COON, R . F . and MERRITT, A . H . , P r e d i c t i n g In Situ Modulus o f D e -f o r m a t i o n U s i n g Rock Q u a l i t y I n d e x e s , D e t e r m i n a t i o n o f t h e In Situ Modu lus o f D e f o r m a t i o n o f R o c k , ASTM STP 4 7 7 , Am. S o c . T e s t i n g M a t s . , 1970 . 2 2 . BROCH, E. and FRANKLIN, J . A . , The P o i n t - L o a d S t r e n g t h T e s t , I n t e r -n a t i o n a l J o u r n a l o f Rock M e c h a n i c s and M i n i n g S c i e n c e s , V o l . 9 , No. 6 , 1972 . 2 3 . HEUZE, F . E . , OHNISHI , Y . , and GOODMAN, R . E . , B o r e h o l e J a c k D e f o r m -a b i l i t y Measurements and S t r e n g t h T e s t i n g o f S e l e c t e d Rocks f r o m t h e Auburn Dam S i t e , R e p o r t t o U . S . Army C o r p s o f E n g i n e e r s , Omaha, N e b r a s k a , 1 9 7 1 . 128 A P P E N D I C E S 129 APPENDIX 1 ANALYSIS OF STRAIN GAUGE CIRCUIT c o m p e n s a t i n g gauge F o r t h e c i r c u i t c o n f i g u r a t i o n shown above D a l l y and R i l e y [ 4 ] have p r e s e n t e d t h e f o l l o w i n g e q u a t i o n ; v AR, AR AR AR ( 1 + r r 1 2 K 3 K 4 w h e r e : AE v o l t a g e o u t p u t f r o m c i r c u i t V v o l t a g e a p p l i e d t o c i r c u i t r R 2 / R ] AR r e s i s t a n c e change o f t h e s t r a i n gauges 1 t h r o u g h 4 R i n i t i a l r e s i s t a n c e o f s t r a i n gauges 1 t h r o u g h 4. 130 F o r t h e c i r c u i t a b o v e : R-| = R 2 = l 2 0 ohms, T h e r e f o r e r = 1 When a s t r a i n i s imposed on t h e t e s t s a m p l e t h e r e s i s t a n c e o f t h e a c t i v e gauges (R - j , R 3 ) w i l l change w h i l e t h e c o m p e n s a t i n g gauges (Rg .R^ ) w i l l show no c h a n g e . T h e r e f o r e A R 2 = AR^ = 0 T h e r e f o r e e q u a t i o n ( l a ) becomes: f - T ' f * i f ' • • • -<2a> A s s u m i n g AR-j = A R 3 and R 1 = R 3 t h e n (2a) becomes: AE = T_ AR V 2 R I t i s a l s o known t h a t : (3a ) f= ( G . F . ) f o r f - = ( G . F . ) e . . . . ( 4 a ) w h e r e : G . F . gauge f a c t o r hi/I = e = s t r a i n 131 C o m b i n i n g (4a) and (3a) y i e l d s : AE = 1 ,r c x n = 2 / AE v T 2 ( G - F ' ) e o r e JGT7) ( T ) In o t h e r w o r d s , t h e f u l l b r i d g e c i r c u i t above i n d i c a t e s t w i c e t h e c o r r e c t s t r a i n , v a l u e s . The a d v a n t a g e o f t h i s c i r c u i t i s t h a t t h e s e n s i t i v i t y o f s t r a i n measurement i s i n c r e a s e d by t h e f a c t o r o f t w o . 132 APPENDIX 2 TIME STUDY OF LABORATORY TESTING PROGRAMME O p e r a t i o n Time ( m i n . / s a m p l e ) 1 . C u t t i n g c o r e w i t h d iamond saw 5 2 . G r i n d i n g c o r e on s u r f a c e g r i n d e r 2 1 / 2 h r . / 1 4 s a m p l e s 11 3 . M e a s u r i n g , w e i g h i n g , l o g g i n g 8 4 . P r e p a r i n g sample f o r gauges 7 5 . A p p l y i n g g a u g e s , t e r m i n a l t a b s 10 6 . S o l d e r i n g l e a d s 10 7. T e s t i n g c o n t i n u i t y , c o a t i n g w i t h s i l i c o n e r u b b e r 2 8 . D e f o r m a t i o n t e s t i n g (2 c y c l e s p e r s a m p l e ) 50 T o t a l 103 m i n . ( a p p r o x i m a t e l y 1 3 / 4 h r . / s a m p l e ) APPENDIX 3 RESULTS OF LABORATORY TESTS 134 APPENDIX 3A QUARTZITE GNEISS ( V a l u e s i n p s i x 1 0 6 ) 1 s t c y c l e 2nd c y c l e 1 s t c y c l e 2nd c y c l e 1 s t c y c l e 2nd c y c l e N l 7 . 2 9 7 . 2 6 8 . 7 5 9 . 5 7 7 . 7 0 7 . 6 8 N4* 5 . 0 5 5 . 2 3 5 . 8 0 6 . 5 0 5 . 4 3 5 . 5 4 N5 7 . 6 3 7 . 6 0 1 0 . 3 9 . 4 7 6 . 9 4 N6 7 . 7 0 7 . 6 4 8 . 9 7 9 . 6 3 8 . 2 2 8 . 2 3 N7 8 . 4 2 8 . 3 2 9 . 5 2 10.1 8 . 9 0 9 . 8 4 N8 6 . 4 5 7 . 0 9 N9 5 . 4 8 5 . 6 0 6 . 8 6 7 . 5 3 5 . 8 3 6 .11 N10 5 . 5 5 5 .51 6 . 6 0 7 . 4 3 6 .11 6 . 1 3 N i l 6 . 6 9 6 . 9 3 8 . 2 8 9 . 0 9 7 . 1 0 7 . 3 7 N12 5 . 5 4 5 . 4 7 8 . 0 6 8 .81 6 . 5 0 6 . 5 4 N13 7 . 0 8 7 . 0 3 8 . 9 8 9 . 5 6 7 . 5 9 7 . 5 8 N14 6 . 8 5 6 . 8 8 8 . 2 6 8 . 6 7 7 . 1 8 7.21 N15 6 . 2 2 8 . 1 9 N16 6 . 3 2 6 . 2 4 7 . 3 9 8 .21 7 .01 6 . 9 7 N17 7 . 1 4 7 .01 8 . 7 4 9 . 2 8 7 . 5 8 7 . 4 9 N18 6 . 8 2 6 . 7 6 8 . 0 9 8 . 6 3 7 . 1 4 7.11 N19 7 . 1 8 7 . 1 3 8 . 5 6 8 . 9 9 7 . 4 8 7 . 4 6 N22 6 . 0 2 5 . 9 9 7 . 1 3 7 . 7 9 6 . 4 6 6 . 4 8 N23 5 . 0 5 4 . 9 8 6 . 8 5 7 . 5 2 5 .61 5 . 5 9 N26 4 .61 4 . 5 8 6 . 7 7 7 . 2 5 4 . 9 4 4 . 9 5 N27 5 . 9 5 5 . 7 7 6 .51 7 . 2 6 6 . 4 6 6 . 3 0 N38 5 .61 5 .71 7 . 1 0 7 . 7 9 6 . 1 5 6 . 2 8 N42 5 . 5 5 4 . 9 8 7 . 2 6 6 . 8 6 5 . 8 8 N56 7 . 9 4 7 . 8 9 9 . 3 3 9 . 9 0 8 . 2 9 8 . 2 6 N57 6 . 2 6 6 .21 7 . 1 9 8 . 0 3 , 6 .71 6 . 7 0 N58 5 . 5 6 5 .51 6 . 6 3 7 . 3 3 5 . 9 6 5 . 9 5 * E r r o n e o u s v a l u e s due t o f a u l t y gauge . APPENDIX 3A ( c o n t i n u e d ) Sample Number N66 N67 N74 N77 N85 N93 N96 N 14 15 16 24 25 3 2 * 33 39 1 s t c y c l e 6 . 4 9 4 . 4 8 7 . 3 3 3 . 9 6 7 . 1 5 5 . 8 9 6 .41 6 . 4 3 6 . 4 6 7 . 3 7 5 . 8 6 8 . 4 2 6 . 0 4 3 . 5 7 7 . 0 9 7 . 6 4 2nd c y c l e 6 . 4 2 4 . 4 9 7 . 2 8 7 . 1 4 5 . 7 4 6 . 3 5 6 . 3 4 6 . 3 4 6 . 7 0 6 . 1 2 6 .01 3 . 4 7 7 . 0 2 7 . 6 0 1 s t c y c l e 7 .61 5 . 4 4 8 . 1 7 5 . 2 3 8 . 5 9 7 . 7 9 7 . 3 4 8 . 6 8 7 . 2 9 9 . 0 6 6 . 9 5 9 . 5 6 7 .01 4 . 4 2 8 . 0 5 8 . 6 8 2nd c y c l e 8 . 2 3 6 . 2 6 8 . 7 9 9 . 2 4 8 . 2 2 8 . 0 0 9 . 1 2 7 . 8 9 8 . 8 8 7 . 8 2 7 .51 5 . 2 2 8 . 7 9 9 . 3 5 1 s t c y c l e 6 . 9 2 5 . 0 2 7 . 6 7 7 . 7 6 6 . 2 6 6 . 8 0 6 . 8 0 6 . 7 2 7 . 7 3 6 . 2 7 6 . 2 4 3 . 9 9 7 . 5 6 7 . 9 2 E r 2nd c y c l 6 . 9 3 5 . 0 6 7 . 6 3 7 . 7 8 6 . 1 4 6 . 7 7 6 . 7 4 6 . 6 3 6 . 5 5 6 . 2 2 3 . 9 4 7 . 5 3 7 .91 * E r r o n e o u s v a l u e s due t o f a u l t y gauge . 136 APPENDIX 3B QUARTZ FELDSPAR SCHIST ( V a l u e s i n p s i x 10°) (S = s t r i k e d i r e c t i o n , D = d i p d i r e c t i o n ) Sample Number E s 1 s t c y c l e E s 2nd c y c l e E w 1 s t c y c l e E w 2nd c y c l e E r 1 s t c y c l e E r 2nd eye N40 -S 1 .04 1 . 0 4 2 . 2 7 2 . 6 9 1 .14 1 .17 N40-D 1.31 1.31 2 . 6 4 3 . 0 5 1 .42 1 . 4 5 N44 -S 2 . 9 7 2 . 9 6 2 .81 3 . 3 6 3 . 3 8 3 . 3 8 N44-D 3 . 6 4 3 . 5 9 3 . 2 7 3.91 4 . 2 2 4 .21 N52 -S 1 .09 1 .09 2 .71 3 . 1 9 1 .34 1 .37 N52-D 1 .02 1 .02 2 . 6 8 3 . 0 7 1 . 2 4 1 .27 N54 -S 0 . 9 9 1 .00 2 . 4 2 2 . 8 7 1 .22 1 .25 N54-D 1 . 1 5 1 .16 2 . 5 3 3 .01 1.41 1 . 4 4 N55 -S 1 .52 1 .49 3 . 2 0 3 . 6 8 1.91 1.91 N55-D 1 .40 1 .37 2 . 9 2 3 . 4 0 1 .74 1 . 7 3 N61 -S 2 . 6 2 2 . 6 0 2 . 4 2 3 . 3 3 3 . 2 3 3.21 N61-D 2 . 8 9 3 . 3 4 5 . 2 7 6 . 0 8 3 .31 3 . 8 3 N69 -S 2 . 0 4 2 . 0 4 4 . 0 3 4 . 4 2 2 . 3 8 2 . 4 0 N69-D 2 . 1 6 2 . 1 5 4 . 1 0 4 . 5 2 2 . 5 4 2 . 5 6 N70 -S 1 0 . 5 1 0 . 5 9 .61 1 1 . 5 12.1 12.1 N70-D 9 . 2 7 9 . 0 7 8 . 1 6 9 . 9 7 1 1 . 0 1 0 . 8 N71 -S 3.41 3 . 3 6 3 . 1 5 4 .01 4 . 0 8 4 . 0 7 N71-D 2 . 7 4 2 . 6 8 2 . 6 6 3 . 5 5 3 . 4 8 3 . 4 8 N75 -S 1 . 5 7 1 . 4 3 1 .83 2 . 5 7 2 . 0 8 1 .96 N75-D 3 . 8 8 3 . 6 7 4 . 8 6 4 .91 4 . 7 0 4 . 5 9 N79 -S 7 . 3 6 7 . 2 6 7 . 2 4 8 . 5 6 8 . 3 8 8 . 3 4 N79-D 9 . 2 5 8 . 5 9 7 . 6 6 8.51 1 0 . 7 1 0 . 0 N89 -S 1 . 4 4 1.41 1 .79 2 . 1 5 1 .66 1 . 6 4 N89-D 1 .07 1 .06 1 . 3 8 1 .72 1 .30 1 .30 N91 -S 8 . 2 7 8 . 2 0 7 . 0 9 9 . 0 3 9 . 9 4 9 . 8 6 N91-D 9 .81 9 . 7 8 8 . 5 5 1 0 . 5 1 1 . 3 1 1 . 3 * E r r o n e o u s v a l u e s due t o f a u l t y gauge . APPENDIX 3B ( c o n t i n u e d ) Sample E c E c E E E E Number s s w w r r 1 s t c y c l e 2nd c y c l e 1 s t c y c l e 2nd c y c l e 1 s t c y c l e 2nd cy i N99 -S 2 .71 2 . 7 0 4 . 0 2 4 . 3 9 2 . 9 3 2 . 9 3 N99-D 2 . 5 8 2 . 5 5 3 . 4 7 3 . 9 3 2 . 8 9 2 . 8 9 N100 -S 1 .19 2 . 4 6 N100-D 0 . 8 6 1 . 7 8 N101 -S 1 .72 1 .72 2 . 9 4 3.11 1 .86 1 .87 N101-D 1 .60 1 .60 2 . 8 2 3 . 0 0 1 .75 1 .76 N102 -S 1 .25 1 . 2 4 2 . 5 5 2 . 7 7 1 . 3 8 1 .39 N102-D 0 . 8 6 0 . 8 5 2 . 3 4 2 . 4 9 0 . 9 5 0 . 9 5 N103 -S 0 . 9 2 0 . 9 0 2 . 6 7 2 . 9 8 1 .07 1 .07 N103-D 1 .36 1 .34 3 . 2 3 3 . 4 5 1.51 1.51 N201 -S 0 . 9 2 0 .81 0 . 7 4 1 .32 1 .27 1 .20 N 2 0 1 - D * 1 . 5 5 1 .56 4 .61 4 . 2 4 2 .11 2 . 3 6 N202 -S 2 . 5 6 2 . 4 0 2 . 8 4 3 . 2 7 2 . 9 9 N202-D 2 . 6 2 2 . 3 8 3 . 3 8 3 . 4 2 3 . 0 4 N203 -S 1 .97 1 . 9 4 2 . 1 8 2 . 7 4 2 . 3 2 2 . 3 2 N203-D 4 . 1 8 4 . 0 9 3 . 6 6 4 . 1 2 4 . 6 0 4 . 5 0 N208 -S 6 . 2 4 6 . 1 7 5 . 4 5 7 . 0 0 7 . 5 7 7 . 5 6 N208-D 8 . 4 9 8 . 2 9 7 . 3 8 9 . 9 2 1 0 . 9 1 0 . 8 N209 -S 0 . 7 2 0 . 7 0 1 .20 1 .49 0 . 9 3 0 . 9 2 N 2 0 9 - D * 0 . 2 7 0 . 2 8 0 . 8 3 1 .64 0 . 4 2 0 . 4 7 * E r r o n e o u s v a l u e s due t o f a u l t y gauge . 138 APPENDIX 3C PEGMATITE ( V a l u e s i n p s i x 1 0 6 ) Sample E_ E E E E E Number s s w w r r 1 s t c y c l e 2nd c y c l e 1 s t c y c l e 2nd c y c l e 1 s t c y c l e 2nd cyi 4 0 * 8 . 4 5 1 2 . 7 N20 4 . 3 9 4 . 3 0 5 .01 5 .91 4 . 7 3 4 . 6 4 N31 4 . 8 9 4 . 9 0 6 . 8 3 7 . 5 5 5 . 1 9 5 . 2 0 N33 4 . 3 2 4 . 2 6 5 . 7 6 7 . 0 9 4 . 8 7 4 . 8 8 N84 3 . 4 3 3 . 4 3 5 . 5 4 6 . 1 7 3 . 9 0 3 . 9 3 N92 2 . 4 3 2 . 4 2 3 . 8 8 4 . 6 4 2 .91 2 . 9 4 A luminum 1 0 . 4 1 0 . 4 1 0 . 4 1 0 . 4 1 0 . 4 1 0 . 4 P r e m a t u r e f a i l u r e , v a l u e s d i s r e g a r d e d . APPENDIX 4 139 EXAMPLE OF STEREOGRAPHIC PROJECTION METHOD UTILIZED WITH THE GOODMAN JACK The f o l l o w i n g d a t a i s used t o i l l u s t r a t e t h e s t e r e o g r a p h i c p r o j e c t i o n method f o r d e t e r m i n i n g t h e s p a t i a l a r r a n g e m e n t o f l o a d i n g d i r e c t i o n s and f o l i a t i o n p l a n e s : 1 . O r i e n t a t i o n o f b o r e h o l e : s t r i k e 180 d e g r e e s , d i p - 4 d e g r e e s , 2 . A n g l e between a x i s o f c o r e and f o l i a t i o n p l a n e a t t h e t e s t l o c a t i o n : 30 d e g r e e s , 3 . Assumed s t r i k e o f f o l i a t i o n a t t h e t e s t l o c a t i o n : 025 d e g r e e s . R e f e r r i n g t o the s t e r e o n e t be low t h e d a t a i s p r o c e s s e d i n t h e f o l l o w i n g manner : N 140 APPENDIX 4 ( c o n t i n u e d ) 1 . The h o l e i s p l o t t e d , p o i n t A on t h e s t e r e o n e t . T h i s p o i n t r e p r e s e n t s n o t o n l y t h e h o l e b u t a l s o t h e p o l e t o t h e p l a n e c o n t a i n i n g t h e l o a d i n g d i r e c t i o n . 2 . The s t r i k e o f t h e f o l i a t i o n i s t h e n marked o f f . A p l a n e p e r p e n d i c u l a r t o t h i s s t r i k e d i r e c t i o n i s p l o t t e d , ( p l a n e r ) The p o l e t o t h e f o l i a t i o n p l a n e must be i n p l a n e r and i s d e t e r m i n e d as f o l l o w s . The known a n g l e between t h e h o l e and t h e f o l i a t i o n i s 30 d e g r e e s , t h u s t h e a n g l e between t h e h o l e and t h e p o l e t o t h e f o l i a t i o n i s 60 d e g r e e s . The s t e r e o n e t i s t h u s r o t a t e d u n t i l t h e a n g l e measured a l o n g a g r e a t c i r c l e between p o i n t A and t h e p l a n e r i s 60 d e g r e e s . The p o l e t o t h e f o l i a t i o n i s a t t h i s p o i n t , ( p o i n t B) 3 . The f o l i a t i o n p l a n e i s t h e n p l o t t e d . 4 . The p l a n e p e r p e n d i c u l a r t o t h e h o l e i s p l o t t e d . By e x a m i n i n g t h e o r i e n t a t i o n c o n v e n t i o n ( s e e F i g u r e 8) t h e l o a d i n g d i r e c t i o n s f o r t h e t h r e e t e s t o r i e n t a t i o n s ( 0 , 4 5 , 90 d e g r e e s ) a r e p l o t t e d w i t h i n t h i s p l a n e . (See p o i n t s TO, T 4 5 , T90 r e s p e c t i v e l y ) . 5 . The t r u e a n g l e between t h e f o l i a t i o n p l a n e s and p a r t i c u l a r l o a d i n g d i r e c t i o n c a n o n l y be measured i n t h e p l a n e w h i c h i s p e r p e n d i c u l a r t o t h e f o l i a t i o n and a l s o c o n t a i n s t h e l o a d i n g d i r e c t i o n . A l s o a l l p l a n e s p e r p e n d i c u l a r t o t h e f o l i a t i o n p l a n e must p a s s t h r o u g h t h e p o l e t o t h a t p l a n e . Thus g r e a t c i r c l e s a r e p l o t t e d t h r o u g h t h e p o l e and each l o a d i n g d i r e c t i o n . (See p l a n e s pO, p 4 5 , p90) 6 . The d e s i r e d a n g l e s a r e measured i n t h e p l a n e s pO, p 4 5 , p90 f r o m t h e l o a d i n g d i r e c t i o n t o t h e p o i n t o f i n t e r s e c t i o n w i t h t h e f o l i a t i o n p l a n e . The r e s u l t s a r e as f o l l o w s : T e s t P o i n t s Measured Between A n g l e ( D e g r e e s ) ( D e g r e e s ) 0 TO t o x 22 45 T45 t o y 56 90 T90 t o z 55 In a d d i t i o n t h e i n f e r r e d o r i e n t a t i o n o f t h e f o l i a t i o n a t t h e t e s t l o c a t i o n i s 025 d e g r e e s s t r i k e w i t h 23 d e g r e e s d i p t o w a r d t h e s o u t h e a s t . APPENDIX 5 GOODMAN J A C K RESULTS APPENDIX 5A GOODMAN JACK RESULTS QUARTZITE GNEISS (Modu lus v a l u e s i n p s i x 1 0 6 ) 143 H o l e Number NX-1 90 NX -6 40 N X - 6 55 N X - 8 40 N X - 8 50 i e n t a t i o n E E E ) e g r e e s ) s w r 0 0 .91 1 .14 3 .01 0 . 8 4 2 . 1 3 2 . 9 2 90 1 .22 1 . 2 8 2 . 6 4 1 .17 2 . 1 7 2 . 5 7 45 1 .14 1 . 3 3 2.61 1 .07 2 . 0 3 2 . 3 0 0 1.51 1 . 6 5 2 . 5 0 1 .46 2 . 1 8 2 . 4 3 1 . 4 3 2 . 1 6 2 . 3 9 90 1 . 3 3 1 .46 2 . 2 6 1 .29 1.91 2 . 2 6 1 . 2 7 1 .97 2 . 2 6 45 1 .27 1 . 3 8 1 .89 1 . 2 3 1 . 6 4 1 . 8 5 1.21 1 . 6 5 1 .85 0 2 . 0 7 2 . 3 0 3 . 7 4 2 .01 3 . 3 4 3 . 7 8 2 . 0 0 3 . 5 9 4 . 0 7 90 2 .01 2 . 0 9 2 . 9 6 1 .96 2 . 5 2 2 . 9 3 1 .96 2 . 5 7 2 . 9 6 45 2 . 0 0 2 . 0 3 3 . 1 6 1 .97 2 . 4 9 3 . 1 6 1 . 9 5 2 . 7 4 3 . 1 0 0 1 .77 1 .92 2 . 7 2 1 .76 2 . 3 8 2 . 7 9 1 . 7 3 2 . 4 0 2 . 6 7 90 1 . 7 8 1 .92 2 . 9 0 1 . 7 4 2 . 4 3 2 . 7 9 1 .72 2 . 4 0 2 . 7 5 45 1 .82 1 .90 2 . 5 8 1 .79 2 . 2 4 2 . 5 8 1 . 7 8 2 . 2 8 2 . 5 4 0 1 . 7 4 1 .89 2 .61 1 . 7 3 2 . 2 2 2 . 3 3 1 .76 2 . 0 5 2 . 6 9 90 1 .70 1.91 2 . 5 2 1 . 6 8 2 . 2 8 2 . 4 3 1 .66 2 . 2 6 2 . 4 8 APPENDIX 5A ( c o n t i n u e d ) H o l e Depth Number ( f t . ) NX -9 45 N X - 1 2 30 NX -12 85 NX-12 95 O r i e n t a t i o n E E E ( D e g r e e s ) s w r 45 1 .90 1 . 9 4 2 . 5 5 1 .90 2 . 3 2 2 . 6 2 1 . 8 8 2 . 3 0 2 . 6 0 0 1 . 7 3 1.91 2 . 8 5 1 . 6 8 2 . 3 9 2 . 7 8 1 . 6 8 2 . 4 7 2 . 7 3 90 1 .87 2 . 1 4 2 . 7 3 1 .86 2 . 3 9 2 . 8 5 1 .84 2 . 4 7 2 . 5 8 45 1 .72 1 . 9 4 2 . 4 0 1 .65 2 . 0 7 2 . 5 0 1 .66 2 . 2 8 2 . 5 4 1 . 6 5 2 . 2 6 2 . 4 6 0 1 . 6 5 1 .94 2 . 5 5 1.61 2 . 3 2 2 . 5 2 1 .59 2 . 3 9 2 . 5 0 90 2 . 0 0 2 . 2 8 3 . 0 7 1 . 9 4 2 . 6 0 2 . 9 8 1 . 9 4 2 . 6 0 3.01 45 2 .01 2 . 1 6 2 . 9 6 1 .96 2 . 4 9 2 . 8 3 1 . 9 5 2 . 4 9 2 . 8 8 1 .80 2 . 4 2 2 . 7 6 0 2 . 4 8 2 . 7 4 4 . 4 0 2 . 3 9 3 . 7 0 4 . 3 4 2 . 3 4 3 . 7 5 4 . 5 8 90 2 . 0 2 2 . 3 0 3 .01 2 .01 2 . 8 7 2 . 9 8 1 . 9 8 2 . 9 0 3 . 1 6 45 2 .01 2 . 2 4 2 . 8 3 1 . 9 8 2 . 6 5 2 . 7 6 2 . 0 0 2 . 7 4 2 .51 0 1 .76 2 . 2 4 3 . 3 5 1 .69 2 . 8 7 3 . 5 0 1 . 6 8 3 . 0 9 3 . 4 2 90 2 . 0 7 2 . 1 8 3 . 3 5 1 .97 2 . 7 4 3 . 1 3 1 . 9 4 2 . 7 7 3 . 1 6 45 1 .69 2 . 0 3 3 . 2 9 1 . 6 8 2 . 9 8 3 . 5 4 1 .66 3 . 2 5 3 . 5 8 APPENDIX 5A ( c o n t i n u e d ) H o l e Depth O r i e n t a t i o n Number ( f t . ) ( D e g r e e s ) N X - 1 3 105 0 90' 45 E r 2 . 4 6 2 .71 4 . 2 8 2 . 3 2 3 . 5 9 4 . 1 2 2 . 2 9 3 . 6 4 4 . 0 2 1 .40 1 .60 2 . 2 0 1 .35 1 . 9 2 2 . 1 7 1 . 3 4 1 .97 2 . 1 7 1 .80 2 . 0 2 3 . 2 2 1 .72 2 .71 2 . 9 4 1 .69 2 . 6 8 3 . 0 7 146 APPENDIX 5B GOODMAN JACK RESULTS QUARTZ FELDSPAR SCHIST (Modu lus v a l u e s i n p s i x 10 ) H o l e Depth Number ( f t . ) NX-1 70 N X - 2 50 N X - 2 55 N X - 2 75 N X - 2 80 j n t a t i o n E c E ;grees) s W r 0 1 . 1 2 1.31 3 . 1 0 1 .06 2 .41 90 1 .13 1 .36 2 . 3 0 1 . 1 0 1 . 9 8 2 . 2 7 45 1 .00 1 .34 3 . 1 4 0 . 9 6 2 . 5 6 3.11 0 1 .33 1 . 5 5 2 . 0 9 1.31 2 . 0 8 2 . 3 3 1 .20 2 . 0 4 2 . 9 2 90 1 .06 1 . 1 5 1 .97 1 .03 1 .59 1 . 9 8 1 .02 1 . 6 3 1 . 9 5 45 1 .50 1 . 6 5 2 .01 1 . 4 8 1 .89 2 . 0 0 1 .46 1 .89 1 .92 0 1 .30 1.51 2 . 0 8 1 . 2 7 1 .92 1 .97 1 .27 1 . 9 4 2 . 0 0 90 1 .10 1 . 2 4 1.91 1 . 0 8 1.71 1 . 9 5 1 .06 1 . 7 4 1 . 9 3 45 1.21 1 .40 2 . 0 4 1 . 1 7 1 .69 1 .92 1 . 1 7 1 .57 2 . 0 0 0 1 . 2 4 1 .20 2 . 1 7 1.21 1 .70 2 . 3 2 1 .19 1 .87 2 .31 90 1 . 0 8 1 .19 2 . 1 9 1 . 0 3 1 .72 2 . 1 6 45 1 .10 1 .17 1 .72 1 .09 1 .56 1 .67 1 . 0 8 1.51 1 .80 0 1.71 1 . 8 3 2 .01 1 .70 1 .92 2 . 1 2 90 1 . 0 7 1 .26 1 .76 45 1 .27 1 .37 2 .01 1 . 2 5 1 .66 1 . 9 8 1 . 2 4 1 .69 2 .01 APPENDIX 5B ( c o n t i n u e d ) H o l e Depth O r i e n t a t i o n Number ( f t . ) ( D e g r e e s ) N X - 3 70 0 90 45 N X - 3 100 0 90 45 N X - 4 45 0 90 45 N X - 4 50 0 90 45 N X - 4 60 0 90 45 E r 1 . 1 3 1.31 2 . 3 2 0 . 8 3 1 . 5 5 2 . 2 2 0 . 6 2 0 . 6 8 1 .50 0 . 4 8 0 . 9 3 1 .45 0 . 3 9 0 . 9 3 1 .47 0 . 7 5 0 . 7 5 1 . 4 4 0 . 5 5 0 . 8 7 1 .37 1 . 2 8 1 . 3 5 1 .83 1 . 2 3 1 .67 1 .80 0 . 8 6 0 . 9 8 2 . 3 7 0 .71 1 .52 2 . 3 7 1 . 0 5 1 .27 2 . 1 6 0 . 8 9 1 .72 2 . 1 5 1 .55 1 . 7 3 3 . 0 8 1 .49 2 . 6 5 3 . 0 2 1 . 4 5 2 . 5 2 2 . 8 7 1 .30 1 .39 2 . 3 6 1 . 2 7 1 . 9 8 2 . 3 0 1 .25 1 . 9 8 2 . 3 4 1 .36 1 .49 2 . 3 8 1 .32 2 . 0 4 2 . 3 4 1.31 2 . 0 8 2 . 3 6 1 . 5 8 1 .60 2 . 8 8 1.51 2 . 3 3 2 . 8 5 1 .49 2 . 4 3 2 . 7 0 1 . 9 5 1 . 8 8 3 . 2 4 1 .89 2 . 7 0 3 . 3 2 1 . 8 8 2 . 8 3 3 . 4 0 1 . 3 3 1 . 4 8 2 . 5 0 1 .29 2 . 0 6 2 . 5 7 1 . 2 7 2 . 1 3 2 . 6 2 1 . 3 2 1 . 7 3 2 . 3 8 1 .24 2 . 1 6 2 . 2 8 1 . 2 3 2 . 2 3 2 . 1 5 1 . 1 3 1 .39 2 . 1 9 1 .07 2 . 0 3 2 . 1 5 1 . 0 4 2 . 0 3 2 . 1 6 1 .62 1 .75 2 . 4 4 1 . 5 5 2 . 1 5 2 . 4 0 1 . 5 3 2 . 2 0 2 . 3 9 APPENDIX 5B ( c o n t i n u e d ) H o l e Depth O r i e n t a t i o n Number ( f t . ) ( D e g r e e s ) N X - 5 30 0 90 45 N X - 5 60 0 90 45 N X - 5 78 0 90 45 N X - 8 60 0 90 45 NX-11 30 0 148 E r 1 . 3 3 1 .45 1 . 9 8 1 .06 1 .59 1 . 9 8 0 . 8 7 1 . 5 8 1 .96 1 .54 1 . 6 7 2 . 0 3 1 .30 1 . 7 7 2 . 1 4 1 .07 1 .76 2 . 0 9 1 .49 1 . 6 5 2 . 0 2 1 .34 1 . 7 5 2 . 0 3 1 . 1 3 1 .75 2 . 0 6 1 .07 1 . 1 7 1.81 1 . 0 3 1 . 4 4 1.71 1.01 1 .45 1 .70 1 . 0 8 1 . 1 3 1 .36 1 . 0 5 1 . 3 5 1 .60 1 . 0 3 1 .39 1 .56 1 .13 1 .20 1 .78 1.11 1 . 5 5 1 . 7 8 1 .10 1 .56 1 . 7 5 1 .42 1 . 4 3 1 .77 1 .40 1 . 6 3 1.91 1 . 3 8 1 . 4 5 1 .93 1 . 3 4 1 .75 1 .92 1 . 3 3 1 .79 1 .89 1 .22 1 . 2 5 1 .87 1 .19 1.61 1 . 8 4 1 . 1 8 1 .62 1 .85 1 . 5 8 1 . 6 8 2 . 5 7 1 .50 2 . 0 2 2 . 9 3 1 . 4 8 2 . 4 8 2 . 7 9 1 .46 2 . 4 3 2 . 7 2 1 .46 1.61 2 . 5 6 1.41 2 .11 2 . 4 7 1 . 3 8 2 .11 2 . 4 2 1 . 5 4 1 .66 2 . 6 9 1.51 2 . 2 4 2 . 6 3 1 .49 2 . 2 6 2 . 6 7 1 .20 1 .40 2 .11 1 . 1 5 1 .76 2 . 1 0 1 .14 1 .76 2 . 1 3 APPENDIX 5B ( c o n t i n u e d ) H o l e Depth O r i e n t a t i o n Number ( f t . ) ( D e g r e e s ) 90 45 N X - 1 3 70 0 90 45 N X - 1 3 80 0 90 45 N X - 1 4 60 0 90 45 NX -14 90 0 149 E r 0 . 7 8 0 . 8 9 1 .35 0 . 7 6 1 . 2 5 1 . 3 8 0 . 7 5 1 .30 1 . 2 3 0 .91 1 .12 1.51 0 . 8 9 1 . 4 8 1.51 0 . 8 8 1 .52 1 .50 1 .20 1 . 3 5 2 . 1 9 1 . 1 7 1 .97 2 . 1 9 1 . 1 5 2 . 0 4 2 . 2 6 1 .46 1 .97 2 . 5 6 1 .40 2 . 4 2 2 . 3 8 1 . 3 8 2 . 5 6 2 . 3 6 1 .17 1 .46 1 .87 1 .15 1 . 6 8 2 . 5 0 1 .14 2 . 3 0 2 . 5 8 1 .14 2 . 3 8 2 . 5 8 1 .17 1 .49 1 .59 1 .15 1 .80 1 .66 1 . 1 5 1 . 8 3 1 .66 2 . 5 6 2 . 5 3 3 .31 2 . 5 6 3 . 1 6 3 . 7 0 2 . 5 2 3 . 3 4 3 .49 2 . 1 8 2 .11 3 . 0 4 2 . 1 5 2 . 5 3 3 . 0 4 2 . 1 2 2 . 4 8 2 . 9 8 0 . 7 0 1 . 1 3 2 . 5 8 0 . 6 8 2 . 6 2 2 . 7 2 0 . 6 8 2 . 9 5 3.TO 1 .76 1 .75 2 . 5 6 1 . 7 3 2 . 2 2 2 . 6 0 1 .72 2 . 2 6 2 . 6 0 1 . 3 4 1 .62 2 . 3 3 1.31 2 . 1 9 2 . 4 4 1 .30 2 . 3 3 2 . 4 2 1 .36 1 . 5 5 2 . 1 7 1.31 1 . 8 5 2 . 1 7 1 .28 1 . 8 5 1 . 5 7 1 .30 1 .77 2 .21 APPENDIX 5B ( c o n t i n u e d ) H o l e Depth O r i e n t a t i o n E E E Number ( f t . ) ( D e g r e e s ) s w r 90 1 . 7 8 1 .85 2 . 6 2 1 . 7 3 2 . 2 2 2 . 6 0 1 .70 2 . 2 2 2 . 5 8 45 1 .40 1 . 7 3 2 . 2 0 1 . 3 7 1 .97 2 . 2 6 2 . 8 5 2 . 0 3 3 .31 N X - 1 5 48 0 1 . 6 5 2 . 0 0 2 . 9 9 1 .55 2 . 6 6 2 . 8 6 90 1 .17 1 .50 2 .41 1 . 1 4 2 . 1 5 2 . 2 2 45 1 .26 1 . 5 3 2 .31 1.21 2 . 0 2 2 . 2 4 151 APPENDIX 5C GOODMAN JACK RESULTS PEGMATITE (Modu lus v a l u e s i n p s i x 10 ) H o l e Depth O r i e n t a t i o n Number ( f t . ) ( D e g r e e s ) N X - 5 45 0 90 45 N X - 7 30 0 90 45 NX -10 30 0 90 45 NX -15 60 0 90 45 E r 1 . 4 5 1.61 2 . 0 0 1 . 4 3 1 . 8 3 2 .01 1 .40 1 .79 2 . 1 8 1 .76 1 . 8 8 2 . 3 2 1 .72 2 . 0 9 2 . 2 8 1 . 6 5 2 . 0 9 2 . 2 9 1 . 5 7 1 .76 2 . 4 3 1 .56 2 . 0 9 2 . 5 0 1 .56 2 . 0 9 2 . 4 8 0 . 8 4 0 . 9 0 1 .52 0 . 8 2 1 .32 1 .52 0 . 8 5 1 .50 1 .70 1 . 5 3 1 . 4 8 3 . 0 2 1 .46 2 . 4 0 2 . 9 2 1 . 4 3 2 . 4 8 2 . 9 5 1 .04 1 . 0 3 2 . 1 2 1 .02 1.71 2 . 2 8 1 . 0 3 1 .89 2 . 3 3 1 .30 1 .37 2 . 2 0 1 . 2 3 1 .49 2 . 0 5 1 .22 1 .76 2 . 1 0 1 .60 1 . 5 3 2 . 5 6 1 . 5 5 1 .97 2 . 4 5 1 . 5 2 1 .97 2 . 4 8 1 .89 1 . 7 3 2 . 5 3 1 .85 2 . 1 6 2 . 5 7 1 .86 2 . 2 2 2 . 6 0 1 .56 1.71 3 . 2 9 1 .50 2 . 8 0 3 . 1 3 1 . 4 5 1 .97 2 . 5 5 1 .39 2 .41 2 . 4 4 1 .42 1.81 2 . 4 8 1 .37 2 .41 2 . 3 9 "@en ; edm:hasType "Thesis/Dissertation"@en ; edm:isShownAt "10.14288/1.0078788"@en ; dcterms:language "eng"@en ; ns0:degreeDiscipline "Materials Engineering"@en ; edm:provider "Vancouver : University of British Columbia Library"@en ; dcterms:publisher "University of British Columbia"@en ; dcterms:rights "For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use."@en ; ns0:scholarLevel "Graduate"@en ; dcterms:title "A comparison of three techniques for the determination of deformation properties of rock"@en ; dcterms:type "Text"@en ; ns0:identifierURI "http://hdl.handle.net/2429/18882"@en .