JAN KUBICA Silesian Technical University, Gliwice, Poland

The behaviour of unreinforced brickwork subjected to shear in a direction normal to the bed joints is still not well understood. One of the essential problems is to describe the effect of compressive stresses on the shear capacity and deformation. Most of the shear tests carried out on masonry walls and other structures have been horizontal shear loading. There is little on vertical shear loading. Clay brick walls without compressive load and with such a load simulated by prestressing were tested. The significant influence of compressive stresses an shear capacity and the boundary value of non-dilatational strain angle has been shown. The shear force non-dilatational strain angle relationship was determined. No influence of compressive stresses on the failure method has been found.