Assessing and managing the risk of earthquake-induced liquefaction to civil infrastructure - Seismic Risk Analysis and Management of Civil Infrastructure Systems - page 111

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Assessing and managing the risk of
earthquake-induced liquefaction to civil
infrastructure
J. F. MIAN, Arup, UK, S. K O N T O E,
Imperial College London, UK and M. FREE, Arup, UK
DOI : 10.1533/9780857098986.1.113
Abstract : This chapter presents a framework for managing earthquake-
induced liquefaction for infrastructure assets using a risk-based approach.
At a site-specifi c level, a design has to demonstrate that the specifi ed
performance criteria can be met, both from a safety and operational
perspective. However, large infrastructure systems such as pipelines,
highways and railways must consider the whole range of geohazards
along their route, of which liquefaction is only one. A framework is
presented for the assessment of liquefaction risk, using existing tools and
methodologies for assessment of both liquefaction hazard and of the
infrastructure response to liquefaction occurrence. The risk framework
considers the likelihood of different modes of liquefaction-induced
ground failure and their consequence to infrastructure systems. The
chapter presents a useful overview of liquefaction risk assessments in
practice, with a focus on simple high-level approaches that support
informed, but not risk-averse, decision making.
Key words : liquefaction, permanent ground deformation, liquefaction-
induced damage, liquefaction hazard, liquefaction risk, risk framework.
5.1 Introduction
Recent destructive earthquakes, e.g. Kobe (1995), Chi-Chi, Taiwan (1999),
Kocaeli, Turkey (1999) and Christchurch, New Zealand (2010 and 2011) are
prime examples of the potential for earthquake-induced liquefaction to
cause signifi cant damage and disruption to civil infrastructure. Numerous
cases of signifi cant damage to buildings, bridges, roads, pipelines and ports
resulting from the failure of the underlying soils were observed in these and
many other earthquakes.
Methodologies and approaches for the assessment of liquefaction poten-
tial are the subject of signifi cant and ongoing research, and this chapter
briefl y summarises some of the extensive body of technical literature in this
area. The assessment of the potential for liquefaction is presented in the
wider context of a risk management framework for civil infrastructure
systems. A risk management approach is important for owners and
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