Quantification of the magnitude 7.3, British Columbia earthquake of June 23, 1946

Abstract

Reliability methods are employed in this paper to analyze the seismic risk to the Vancouver metropolitan region in Canada. The use of reliability methods contrasts with several contemporary approaches for risk analysis. In this paper, two analysis approaches are presented and implemented in a new computer program. One utilizes the first-order and second-order reliability methods together with a hazard combination technique. The other is a sampling-based method that repeatedly generates damage scenarios in the time period of interest. Both strategies employ the same collection of probabilistic models for seismic risk analysis. While the models are presented in the companion paper, this paper presents the analysis options and a comprehensive application that comprises 559 random variables and 3227 model objects. The primary result is the loss curve, which exposes seismic loss probabilities and serves as a basis for risk mitigation decisions. It is found that the probability of loss in excess of $100 billion in the next 50 years is 5.6%. By-products of the analysis provide further insight; the most vulnerable municipalities and the most influential hazard sources are identified.