W Jäger and P Schöps
Faculty of Architecture,Chair of Structural Design, Dresden University of Technology

The verification of shear walls starts with the search for the weakest point. The shear strength, which is dependent on the material as well on the stress state, has to be calculated for this point. Subsequently the shear-load-capacity of the related cross section area has to be defined. The distribution of the shear stresses over the cross section is mostly assumed to be uniform. This is a simplification and is based on the assumption of the “smearing” of shear due to plasticity. In order to verify the validity of this assumption, the stress distribution was established experimentally. The vertical load was varied in the different tests. One of the walls collapsed due to failure in the joints; another wall exhibited a tension failure in the masonry units. The distribution factor was in both cases greater than one. The experimental results were compared with numerical simulations. In addition a theoretical approach with a plastic material law based on the classical bending theory has been derived in order to analyse the influence of plasticity on the shear distribution-factor. The results are relevant for the recalculation of shear tests and for knowledge of the real behaviour of shear-stiffening in buildings.