An overarching framework to assess the life-time resilience of deteriorating transportation networks in seismic-prone regions

Abstract

This study develops a comprehensive framework to assess the resilience of transportation networks consisting of deteriorating bridges subjected to earthquake events. For this purpose, the structural capacity of highway bridges is estimated during their service life using a set of detailed finite-element models that simulate the progress of deterioration. The developed models take into consideration the main environmental stressors and determine the extent of capacity loss as a function of time. Based on the degraded state of structural components, seismic fragility analyses are performed to obtain a probabilistic evaluation of the extent of damageability of the existing bridges under seismic events. Since each transportation link normally consists of a number of bridges, the state of damage in the individual bridges is mapped to the corresponding links and a scenario-based approach is employed to estimate the resilience of the entire transportation network. To demonstrate how the consequences of structural degradation can be integrated into the developed framework, the large-scale transportation network of Los Angeles and Orange counties is investigated under a series of aging and earthquake scenarios. The outcome of this study indicates how the estimates associated with the functionality measures of a transportation network can be improved if the age factor is properly integrated into the framework used for resilience assessment.