Probabilistic seismic hazard analysis of civil infrastructure - Seismic Risk Analysis and Management of Civil Infrastructure Systems - page 1

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Probabilistic seismic hazard analysis of
civil infrastructure

G. M. ATKINSON, Western University, Canada and
K. G O DA, University of Bristol, UK

DOI : 10.1533/9780857098986.1.3

Abstract : This chapter summarises the past and current developments of
probabilistic seismic hazard analysis, which forms the fundamental basis
for many modern earthquake design code provisions and practices. A
focus is given to an approach based on Monte Carlo simulation, because
it offers fl exibility and rigorousness in the assessment. The method is
explained by following a step-by-step procedure and by using a recent
case study for western Canada. Two illustrations, related to liquefaction
triggering analysis and seismic vulnerability analysis, are discussed to
demonstrate how probabilistic seismic hazard analysis facilitates
advanced earthquake engineering applications.

Key words : probabilistic seismic hazard analysis, probabilistic seismic risk
analysis, performance-based earthquake engineering, uncertainty,
liquefaction.

1.1 Introduction: past developments and current

trends in assessing seismic risks

Probabilistic seismic hazard analysis (PSHA) is concerned with the evalu-
ation of the likelihood of strong ground motion intensities (Cornell, 1968;
McGuire, 2004, 2008), which may cause destruction of buildings and infra-
structure and disruption of economic and social activities. Popular measures
for quantifying ground motion intensity include peak ground acceleration
(PGA), peak ground velocity (PGV), and spectral accelerations (SAs) at
different vibration periods. One of the most important features of PSHA
is a comprehensive accounting of uncertainties related to earthquake occur-
rence, source rupture, wave propagation, and site effects by integrating
hazard contributions over all scenarios. Over the past decades, the PSHA
methodology has evolved signifi cantly by incorporating more detailed and
extended components, such as seismic hazard deaggregation (McGuire,
1995), nonlinear site response analysis (Bazzurro and Cornell, 2004), vector-
value PSHA (Baker and Cornell, 2005), near-fault effects (Tothong et al. ,
2007), and aftershock hazard (Yeo and Cornell, 2009). The outputs from
site-specifi c PSHA are seismic hazard curves (i.e. plot of expected ground

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