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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, long-term material deterioration might have an important impact on seismic damage to bridges. Therefore, it is important to study both independent and interacting hazards and their effects on the reliability and risk of bridges and bridge networks. Although earthquake is still a dominant hazard to bridges in many earthquake-prone countries, a life-cycle reliability and risk approach has to consider both independent and interrelated hazards causing bridge failure. Such an approach is presented in this 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. [ABSTRACT FROM AUTHOR]

The evacuation behavior observed in Kesennuma City, Tohoku, Japan during the Great East Japan Earthquake and Tsunami and a corresponding evacuation simulation are presented. We first organized the damage and evacuation behaviors observed in the target area using the results of previous studies and official surveys. In addition, we compiled all available multimedia sources recording evacuation behavior during the 2011 event to identify the precise temporal and spatial details of the evacuation behavior. Then, a tsunami evacuation simulation was developed based on all compiled evacuation data, considering the tendencies regarding the use of main roads for evacuation, residents' shelter preferences, and pedestrian-car interactions. The developed simulation was validated against the compiled evacuation behaviors by inputting the estimated initial conditions of the 2011 event. The traffic scenarios calculated in the simulation closely reproduced the actual traffic flow as observed from the evacuation data. The evacuee populations at several shelters in the simulation also quantitatively reproduced the trend of the real numbers of evacuees reported by Kesennuma City. The results of the simulation exhibited a better capability to estimate the actual evacuation behavior during the 2011 event than that achieved in previous studies. [ABSTRACT FROM AUTHOR]