UBC Theses and Dissertations
A stiffness model for plane stress analysis Hibbert, Paul D.
The stiffness properties of a finite sized square model element of an isotropic plate under plane stress are presented. The model is a piece of the material itself and not a configuration of bars that replace the material. It is shown that the use of an extra kinematic condition instead of an arbitrary displacement function usually produces better results. An example shows that this extra condition greatly increases the accuracy of the model and so reduces the number of degrees of freedom required to approximate the continuous system. A system of bounding the solution is shown by assigning values to free parameters. Thus the maximum error is known and can be reduced without going to a fine grid. The derivation of the isotropic square is then expanded to obtain the stiffness matrix of an elemental orthotropic rectangle. The limits of stability for both the isotropic and orthotropic models are investigated.
Item Citations and Data