Limit-state design for shear in rectangular and T beams

Synopsis The four major modes of shear failure—diagonal tension, shearing, shear-compression and web crushing—are discussed briefly and equations are given for predicting resistances to them. The larger part of the paper is devoted to two other design criteria. An analytical approach to shear cracking at vertical web-flange junctions is outlined and its predictions are compared with the results of a limited group of tests by the authors. A semi-empirical equation is derived for the calculation of limit state of local damage resistance as determined by widths of shear cracks, and is compared with more extensive test data for various types of beam tested by the authors and others.