Expeditious Methods for the Out-Of-Plane Seismic Safety Assessment of URM Walls in Europe

Traditional masonry constructions are extremely vulnerable to seismic events, affecting the development of many countries around the world. The out-of-plane (OOP) seismic response of masonry walls is one of the most complex and ill-understood areas of seismic analysis. Post-earthquake observations have identified OOP collapse as one of the main failure modes in unreinforced masonry buildings (URM) and most of these occur due to inadequate design or construction. Furthermore, even though current seismic safety assessment codes emphasize the use of nonlinear analysis methods, most professionals still rely on linear-elastic analysis due to its simplicity. The present work contributes to the seismic safety assessment of the out-of-plane behavior of unreinforced masonry walls through a displacement-based approach, providing the capacity for different out-of-plane geometric indexes and its seismic response in different earthquake-prone regions in Europe. The analyses are conducted using a seismic probabilistic framework, considering the most common out-of-plane mechanisms, different material properties, various slenderness ratios, and a wide range of seismicity levels to cover the seismic hazard in Europe. The results presented can be useful for seismic safety assessment by providing simple relationships to compute the capacity and the seismic demand in compliance with the seismic action in the European standard.