URM Structures Failure Modes

This lecture covers the failure mechanisms of unreinforced masonry (URM) structures, focusing on the in-plane and out-of-plane failure modes. It discusses the seismic engineering aspects related to URM walls, including the strength capacity, effective stiffness, and drift capacity. The presentation also includes a detailed analysis of the strength capacity according to different codes and the Swiss code (SIA 266). Various failure modes such as flexural failure, shear failure, and diagonal shear failure are explained. Additionally, the lecture explores the drift capacity of URM walls and the factors influencing it, such as axial load ratio and shear span. Case studies of modern URM buildings and stone masonry aggregates are presented to illustrate the practical implications of the discussed concepts.