Life-cycle reliability ofbridges under independent and interacting hazards

After recent large earthquakes, field investigations confirmed that several bridges were severely damaged and collapsed not only due to the earthquake, as an independent hazard, but also to the subsequent tsunami, landslide or fault displacement. In addition, material deterioration might cause further seismic damage to bridges. Therefore, it is important to study both independent and interacting hazards and their effects on the reliability of bridge and bridge networks. Although earthquake is still a dominant hazard to bridges in many earthquake-prone countries, a life-cycle reliability approach has to consider both independent and interrelated hazards causing bridge failure. Such an approach is presented in this keynote paper. In addition, issues related to life-cycle analysis, design, risk, resilience and management of bridges under earthquake and other hazards are discussed. Finally, the concepts and methods presented are illustrated on both single bridges and bridge networks.