The end panel of a plate girder is analysed for plastic collapse under high shearing load by means of the upper bound theorem. Two possibilities are considered for the behaviour of the web: either (a) it remains unbuckled or (b) it develops a full plastic tension field. Curves are presented showing how the collapse load depends on the dimensions and on a parameter signifying the full plastic bending strength of the flanges in relation to the web strength. In general, the numerous experimental results available in the literature lie between the predictions based on (a) and (b) respectively.
C.R. Calladine