Effect of Soil–Structure Interaction on Inelastic Displacement Ratios of Bridge Structures Subjected to Pulse-Like Ground Motions

Abstract

This study aimed to investigate the effect of soil–structure interaction (SSI) on the inelastic displacement ratio of bridge structures subjected to near-fault pulse-like earthquake ground motions. SSI was modeled using a discrete-time recursive filter approach and frequency-dependent foundation–soil impedance functions. A total of 105 near-fault earthquake ground motion records were used for the analysis. The study also compared the soil–foundation–superstructure (SFS) system with a fixed-base system to explore the effects of spectral period normalization, strength reduction factor, earthquake magnitude, site-to-source distance, and peak ground velocity on the inelastic displacement ratio. The findings indicate that both the SFS and fixed-base systems have significant inelastic displacement demand under near-fault earthquakes, with values that can be 2–3 times higher than those predicted by ASCE-41-13, particularly in the short period range. Furthermore, as the structural period approaches the earthquake pulse period, the SFS system generally shows larger inelastic displacement ratios compared to the fixed-base system. The analytical results provide insight into the factors affecting the inelastic displacement ratio for near-fault pulse-like earthquakes.

Shaking Tables Test on Seismic Responses of a Long-Span Rigid-Framed Bridge Considering Traveling Wave Effect and Soil–Structure Interaction

“…For example, Sung Y.C. et al [13] investigated the effect of the soil-structure interaction on the inelastic displacement ratio of bridge structures subjected to near-fault pulse-like earthquake ground motions. Das S. et al [14] conducted a comparative case study of seismically vulnerable surfaces of rail-bridge piers with and without soil-structure interaction.…”

“…It has been shown that the mechanism of considering the effect of the soil-structure interaction on the seismic response of large-span bridge structures is very complex, and is closely related to the input ground vibration field characteristics [13,16,17], foundation soil properties [15,[18][19][20], and the structural form of the bridge [14,17,21]. The effect of the interaction on the structure is dependent on their relative properties.…”

“…The effect of the interaction on the structure is dependent on their relative properties. In experimental studies, numerical simulations are used normally to study the seismic response of longspan bridges with the limitations of the test site and test equipment [13,14,16,21]. There are rarely experimental studies considering the effect of the soil-structure interaction on the seismic response of long-span bridges.…”