Seismic resilience of bridges in transportation networks

A disproportionate collapse can be avoided by improving collapse resistance, reducing the vulnerability of the structure or increasing structural robustness. While vulnerability depends on the individual structural components, robustness depends on the whole structural system. Besides collapse resistance, a disproportionate collapse can also be prevented by reducing the exposure of the structure to external actions. Robustness of buildings and bridges is defined as the insensitivity of a structure to the initial damage. Such characteristic has been recognized as a desirable in structural systems, being able to exclude progressive and disproportionate collapses. The robustness of bridges is investigated in this research work at the numerical level by employing a model of a cable-supported bridge. Several earthquake records are employed for the robustness assessment of the bridge at increasing intensity. The role of the redundancy in the structural scheme of the bridge is then evaluated as the strategic measure for limiting disproportionate collapses and improving robustness. Furthermore, solutions for reducing the time for recovering functionality, after the damage occurrence, are also evaluated and discussed within a resilient community framework. Indeed, this study can provide valuable information that can facilitate decision making, enhance planning for disaster mitigation and recovering of critical infrastructures as the transportation network, reducing social and economic losses.