Stochastic modeling of deterioration in buildings and civil infrastructure - Seismic Risk Analysis and Management of Civil Infrastructure Systems - page 403

16
Stochastic modeling of deterioration in
buildings and civil infrastructure
R. KUMAR, Texas A&M University, USA a n d
P. GARDONI, University of Illinois at
Urbana-Champaign, USA
DOI : 10.1533/9780857098986.3.410
Abstract : Infrastructure systems deteriorate while in service due to
routine use and exposure to extreme conditions (e.g., earthquakes and
corrosive environment). Deterioration is a serious concern as it can
considerably reduce the structural capacity and consequently the
reliability and service life of systems. Moreover, deterioration is a highly
uncertain process and is often invisible. This chapter fi rst presents the
stochastic modeling of a general deterioration process. Then, as an
illustration, the chapter conducts a stochastic analysis of the structural
deterioration process of a typical single-column reinforced concrete
(RC) highway bridge that is subject to deterioration due to corrosion
and earthquakes. In particular, the illustration considers the
deterioration of the bridge column due to loss of lateral stiffness,
low-cycle fatigue of longitudinal reinforcement and loss of cross-
sectional area of reinforcing steel. The presented method is general and
can be applied to analyze other structural systems experiencing different
deterioration mechanisms.
Key words : stochastic modeling, structural deterioration, reinforced
concrete. (RC) bridges, infrastructure systems, earthquakes, corrosion
16.1 Introduction
Civil infrastructure systems are critical to the functioning of a country; they
are expensive to build and their disruption often leads to severe conse-
quences. Civil infrastructure systems are often subject to extreme environ-
mental conditions causing them to deteriorate. In order to optimize the
long-term reliability and life-cycle cost of infrastructure systems, we need
to develop methods to model deterioration processes accounting for the
relevant uncertainties. Moreover, since in the fi eld of civil engineering, the
interest in performance-based engineering is growing, we need such models
to be able to predict the long-term performance of infrastructure systems.
In the area of reliability and performance of deteriorating systems,
researchers have broadly conducted two types of studies. In the fi rst type,
studies primarily computed the reliability of systems at various stages of
deterioration using laboratory test data and complex numerical modeling
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