Performance-based multi-hazard evaluation of benchmark tall building via simplified nonlinear models

This study examines the nonlinear dynamic response of archetype tall buildings ( H-B-D = 5–1–1, T = 5 s) subjected to recurring earthquakes and winds in both single- and multi-hazard environments. Idealized two-degree-of-freedom models calibrated with smooth plasticity Bouc-Wen hysteretic elements are employed to analyze the coupled lateral behavior under biaxial earthquake excitation, alongwind, and crosswind loads. Nonlinear response history analyses are performed using hazard-consistent seismic motions (FEMA P-695 near-fault suite) and wind histories derived from high-fidelity wind tunnel data (Tokyo Polytechnic University aerodynamic database), enabling the capture of system responses across various limit states up to collapse. A parametric study investigates how key model parameters - such as yield displacement ratio, strain hardening ratio, and hysteretic degradation - affect peak displacement demands, ductility responses, and energy dissipation capacity. Fragility analyses under single- and multi-hazard scenarios reveal distinct probabilities of exceeding various seismic and wind damage states, differentiating the vulnerability of ductile, semi-ductile, and non-ductile designs. The results demonstrate the effectiveness of limited ductility design strategies for wind loads, aligning with recent performance-based wind design provisions and maintaining consistency with seismic ductility requirements. Lastly, the study discusses the development and calibration of wind response modification factors.