Seismic fragility analysis of pile-supported wharf in nearshore liquefiable ground

The seismic fragility analysis has become a research hotspot in structural engineering and bridge engineering, but there are few studies in the field of pile-supported wharf in nearshore liquefiable ground. Based on the typical engineering examples, a numerical model for seismic response analysis of all-straight pile and pile-supported wharf in nearshore liquefiable ground is established. In view of bending failure and bending shear failure, through the modal analysis and pushover analysis, the damage evolution process of pile-supported wharf and the quantitative discrimination criteria for each damage stage are proposed. With PGA as the ground motion intensity index, 14 groups of typical ground motions are selected and scaled to 8 different intensity levels. With the aid of the incremental dynamic analysis, the IM-EDP curve of the pile-supported wharf in nearshore liquefiable ground is proposed. Based on the proposed criterion for determining the damage of pile-supported wharf, the seismic fragility curve of pile-supported wharf is derived. The cumulative distribution function of log-normal distribution is used to fit the seismic fragility curve, and a simplified seismic fragility curve of pile-supported wharf is proposed for practical application. This work may provide important theoretical basis for the seismic reinforcement of pile-supported wharf in nearshore liquefiable ground.