Performance-based liquefaction analysis and probabilistic liquefaction hazard mapping using CPT data within the Fraser River delta, Canada

Since the Fraser River delta is affected by multiple seismic sources, the selection of a single combination of magnitude and maximum ground acceleration to evaluate liquefaction initiation is challenging. In this study, we use a probabilistic seismic hazard analysis to account for all earthquake scenarios and also consider the liquefaction model uncertainty and soil resistance uncertainty using 787 CPT data across the study area. Hazard curves are generated for the factor of safety against liquefaction (FS L ) and the amount of required soil improvement to prevent liquefaction (Δq L ) which provide a comprehensive assessment of liquefaction triggering. We derive the FS L and Δq L values corresponding to return periods of 475 and 2475 years and generate the first probabilistic liquefaction hazard mapping for the region. Most of the lowland areas of Metro Vancouver correspond to low FS L and therefore soil improvement is needed for liquefaction mitigation. • A performance-based liquefaction analysis accounts for all earthquake hazards. • Key parameter uncertainities are accounted for in the presented probabilistic liquefaction methodology. • The probabilistic liquefaction hazard mapping offers a preliminary assessment for soil improvement applications.