Near-Collapse Drift Capacity of Curved Masonry Walls: Experimental and Numerical Investigation

Lateral drift capacity is a critical parameter in the seismic evaluation of unreinforced masonry (URM) walls. Although many previous studies have explored the factors influencing the drift capacity of straight URM walls, comparatively little research has focused on masonry walls curved in plan, which are frequently encountered in historic structures. To address this gap, the present study first carried out a quasi-static reverse cyclic test on a full-scale curved masonry wall. The experimental results demonstrated asymmetric drift capacities under positive and negative loading directions. Based on these observations, a detailed numerical parametric study of curved URM walls was undertaken. The results indicate that drift capacity increases with greater wall thickness and higher aspect ratio, while it decreases with increasing wall height and masonry compressive strength. Walls with lower aspect ratios were found to be more prone to diagonal shear cracking, particularly when thinner, suggesting increased vulnerability to shear-dominated failure. Using the numerical database generated in the study, an empirical model was proposed to predict the lateral drift capacity of curved masonry walls. Overall, the findings provide valuable insights for the displacement-based seismic assessment and conservation of historic curved masonry walls, and for the design of new curved masonry walls.