UBC Theses and Dissertations
The seismic response of a timber frame with dowel type connections Frenette, Caroline D.
The purpose of this study was to analyse the dynamic behaviour of timber structures with moment resisting connections. The response of ductile dowel connectors and their effect on the seismic behaviour of semi-rigid timber frames were exarnined. Experimental results from component and frame tests were compared with analytical predictions from two different analytical models. The modelling of dowel type connections based on fundamental material properties was achieved and its incorporation in a dynamic frame analysis program has been investigated. To observe the overall non-linear dynamic behaviour of semi-rigid timber frames with dowel type connections, a two-storey test specimen was subjected to simulated ground motion produced by a shake table. The test specimen consisted of two planar moment resisting timber frames braced together in the out-of-plane direction. The beams and columns, composed of parallel strand lumber (Parallam®), were connected using steel plates and tightly fitting steel dowels. The behaviour of one typical connection was monitored in detail in addition to data pertaining to the overall response of the system. Prior to this shake table test, materials and connections properties were studied through monotonic and cyclic tests. To enable the modelling of timber frames with dowel type connections, a finite element model that simulates the non-linear behaviour of the connector caused by yielding of the dowel and crushing of the wood was used. This connector model was included in a two-dimensional static frame analysis program to predict the non-linear response of semi-rigid timber frames. Specific attention was paid to the multi-cycle behaviour of a multiple connector joint. This model was developed and calibrated using test results of dowel connections subjected to cyclic loads. The ultimate goal of modelling the dynamic behaviour of any timber structure joined with dowel type connectors and steel or wood plates, using basic material properties, was investigated. A comparison of the experimental data with the simulated analytical response for the timber frame enabled the verification of various programs, such as SAP90\and DRAIN-2DX, and aided in the calibration of the connection model under dynamic conditions.
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