Incremental dynamic analysis (IDA) applied to seismic risk assessment of bridges - Seismic Risk Analysis and Management of Civil Infrastructure Systems - page 553

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Incremental dynamic analysis (IDA) applied to
seismic risk assessment of bridges
P. TEHRANI and D. MITCHELL, McGill University,
Canada
DOI : 10.1533/9780857098986.4.561
Abstract : This chapter focuses on the use of incremental dynamic
analysis (IDA) for seismic performance and risk assessment of
reinforced concrete bridges. Different record selection methods,
including the epsilon-based, conditional mean spectrum (CMS)-based
and uniform hazard spectrum (UHS)-based methods, are used for the
prediction of the structural responses using IDA. In addition, the
infl uences of including different earthquake types (i.e., crustal,
subduction interface and inslab earthquakes) on the IDA results are
studied. Guidelines for determining different damage states in bridge
columns and developing fragility curves are provided. The important
aspects of structural modelling of bridges for IDA are presented and
the use of IDA for the seismic risk assessment of a 4-span bridge is
demonstrated through an example.
Key words : incremental dynamic analysis (IDA), seismic risk, seismic
performance, bridges, record selection, conditional mean spectrum
(CMS), damage states, fragility curves.
21.1 Introduction
Seismic risk can be expressed as the potential economic, social and envi-
ronmental consequences of seismic events that may occur in a specifi ed
period of time. In order to quantify the seismic risk associated with a certain
structure, one needs to combine two important elements: seismic hazard
and seismic fragility analyses. The determination of the seismic hazard is
accomplished by using conventional probabilistic seismic hazard analysis
(PSHA). For fragility analysis it is essential to predict the general behav-
ioural aspects, consistent with experimental studies (e.g., Banerjee and Shi-
nozuka, 2008a,b; Straub and Der Kiureghian, 2008). Fragility analysis for
bridges is typically carried out using nonlinear dynamic or static analysis,
such as incremental dynamic analysis (IDA) (Vamvatsikos and Cornell,
2002) and probabilistic seismic demand analysis (PSDA) (e.g., Gardoni et al. ,
2003; Karim and Yamazaki, 2003; Lupoi et al. , 2003; Mackie and Stojadi-
novic, 2003; Nielson and DesRoches, 2007a,b; Padgett and DesRoches,
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