Spatial correlation of ground motions in estimating seismic hazards to civil infrastructure - Seismic Risk Analysis and Management of Civil Infrastructure Systems - page 55

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Spatial correlation of ground motions in
estimating seismic hazards to
civil infrastructure
V. S O K O L O V and F. WENZEL,
Karlsruhe Institute of Technology (KIT), Germany
DOI : 10.1533/9780857098986.1.57
Abstract : During the last decade the attention given to studies of
ground-motion correlation has grown. It is related to similarity of
ground-motion variability, or residuals between observations and results
of modeling, for different earthquakes (between-earthquake correlation)
and different locations (within-earthquake correlation). The proper
treatment of ground-motion correlation is essential for the estimation of
seismic hazard, damage and loss for widely located building assets
(portfolios) and spatially distributed structures (lifelines). The goal of
this chapter is to summarize the recent advances of ground-motion
correlation studies, and to provide a list of key references.
Key words : strong ground motion, correlation, seismic hazard and loss.
3.1 Introduction
In the past decade increasing attention has been focused on studies of
ground-motion correlation. There has been a focus on similarity of ground-
motion variability, or differences between observations and results of
modeling, for different earthquakes (between-earthquake correlation) and
different locations (within-earthquake correlation). The correlation of
ground-motion residuals refl ects a non-random component in the residuals,
which is caused by factors not accounted for by the ground-motion model
and which therefore constitutes epistemic uncertainty (attributable to
incomplete knowledge) that may be reduced, in principle. Parameters of
the probability distribution function for the loss to a portfolio (e.g., fractiles
and standard deviation) during an earthquake, which are very important
for decision making and mitigation activities, are affected by ground-motion
uncertainty and correlation. Therefore the consideration of ground-motion
correlation is essential for the estimation of seismic hazards, damage and
loss for widely-located building assets (portfolios) and spatially-distributed
structures (lifelines) (see reviews in Sokolov and Wenzel, 2011a,b). This
chapter summarizes the recent advances in ground-motion correlation
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