Regional liquefaction-induced ground displacement predictions for Canada using 5th Generation NBCC Seismic Hazard Model

Abstract

Significant regions of Canada are seismically active, and areas underlain by loose, saturated sediments in these regions are expected to experience liquefaction-induced lateral spread permanent ground displacements (PGDs) under earthquake shaking. The empirical predictive equations are commonly used for estimating the PGDs especially when detailed numerical analyses are not undertaken. The key input parameters for these equations comprise earthquake magnitude (M) and source distance (R), along with geotechnical and topographic parameters; however, there is ambiguity over choosing appropriate site-specific values of M and R. The current study predicts PGD probabilistic hazard curves that are applicable for locations in southwestern and southeastern regions of Canada using a probabilistic seismic hazard assessment (PSHA) framework. This was achieved by embedding two relevant empirical models for predicting lateral spread PGDs (replacing the ground motion prediction equations) within the 2015 National Building Code of Canada framework that is currently available in OpenQuake platform. Moreover, deaggregation analyses have been performed to understand the M and R contributions from different seismic sources on the predicted site-specific hazard. The developed PGD curves can be readily adopted for estimating site-specific lateral spread PGD demand as input to performance-based design of structures in seismically active areas of Canada.