  The safety and condition of transportation infrastructure has been at the
forefront of national debates in recent times due to catastrophic bridge
failures, but the issue has been a longstanding challenge for transportation
agencies for many years as resources continue to diminish. The performance of
this infrastructure has a direct influence on the lives of most of citizens in
developed regions by providing a critical lifeline between communities and the
transportation of goods and services, and as a critical component of the
transportation network, bridges have received a lot of attention regarding
condition assessment and maintenance practices. Despite successful
implementation of advanced evaluation techniques, what is still lacking is a
fundamental understanding of the system behavior in the presence of
deteriorating conditions that can be used for preservation decision-making.
This paper aims to present a performance-based framework that can be used to
characterize the behavior of in-service bridge superstructures. In order to
measure the bridge system performance with deteriorating conditions,
system-level behavior of a representative composite steel girder bridge,
degraded with three common damage scenarios was investigated in this study.
Results obtained from validated numerical analysis demonstrated significant
impact of integrated damage mechanisms on the ultimate capacity, redundancy and
system ductility of the simulated bridge superstructure. It is expected that
the proposed framework for evaluating system behavior will provide a first step
for establishing a critical linkage between design, maintenance, and
rehabilitation of highway bridges, which are uncoupled in current
infrastructure decision-making processes.
