Nonlinear Seismic Analysis of Elevated Rectangular Metallic Silos Subjected to Multiple Earthquakes

This study investigates the nonlinear seismic response of elevated rectangular metallic silos subjected to sequential earthquake events, incorporating soil–structure interaction (SSI) and the influence of granular material fullness levels. Using three-dimensional (3D) finite element modeling and real seismic sequences recorded within short time windows, the study evaluates the effects of repeated earthquakes on maximum displacement, residual deformation and base shear. The analysis explicitly incorporates flexible elastic foundation systems to account for SSI effects, which significantly influence dynamic behavior. While considerable research exists on cylindrical silos, the seismic performance of rectangular configurations under multiple consecutive earthquakes remains poorly understood. The research systematically compares structural behavior and deformation patterns under single earthquake events versus multiple consecutive seismic sequences. The results demonstrate that consecutive seismic events produce significantly more severe structural responses than individual earthquake occurrences, with sequential earthquakes leading to amplified residual deformations (30–45% higher), increased stress concentrations in critical regions, and progressive degradation of structural capacity. These findings indicate that conventional single-event seismic design approaches may underestimate the vulnerability of rectangular silos in seismically active areas by approximately 30–40%, highlighting the critical importance of considering multiple-event scenarios in performance-based assessment and design procedures.