Abstract
The yield line method is a simple and versatile method for the evaluation of the collapse load of slabs. It has the disadvantage that for all but the simplest examples it requires a tedious search for the potential modes of collapse, each of which must be investigated so that the mode which corresponds to the lowest upper bound to the collapse load may be identified. To overcome the difficulty, several authors have attempted to develop a computer procedure. The drawbacks of their approach have been either the requirement of voluminous input data or the arbitrary and manual search for new yield line patterns in successive iterations. In the present work the equations required for the yield line analysis of the edge supported slabs are presented so as to implement the procedure in a computer program. The search direction to obtain a new pattern in successive iterations is based on a nonlinear simplex algorithm. The procedure is illustrated with the help of numerical examples. A complete listing of the software package written in FORTRAN is given in an appendix.