Comparative Pushover Analysis and IDA-Derived Fragility of RC Shear Walls With and Without Openings

Reinforced concrete (RC) shear walls are primary lateral force-resisting elements in seismic regions; however, architectural openings and height variations reduce stiffness, strength, and deformation capacity, increasing seismic vulnerability and losses. This study evaluates five cantilever RC shear wall configurations: three 3.0~m-high walls (solid, centrally perforated, and staggered openings) and two solid walls with heights of 2.0~m and 4.0~m. Layered-shell models are developed in OpenSees and validated against SAP2000 through comparison of global capacity curves. Nonlinear static pushover analyses are performed to estimate performance points using ASCE/SEI~41, the ATC-40 Capacity Spectrum Method, and the N2 method, and are benchmarked against Incremental Dynamic Analysis (IDA) using the scaled LACC North ground-motion record up to 3.0~g. IDA-based drift--spectral acceleration relationships are used to derive lognormal fragility functions for Immediate Occupancy, Life Safety, Collapse Prevention, and Failure limit states, which are integrated with seismic hazard and consequence models to estimate expected annual loss and 50-year discounted life-cycle costs. Results show that solid walls achieve the highest stiffness and strength, while centrally perforated walls experience the earliest degradation, with staggered openings exhibiting intermediate behavior. Openings shift fragility curves toward lower intensities, resulting in two- to three-fold increases in seismic losses. The study demonstrates that opening layout governs seismic performance and highlights the value of fragility- and life-cycle-based metrics beyond prescriptive code limits.