FRAMEWORK FOR ESTIMATING THE RELIABILITY OF BRIDGES AND EMBANKMENTS UNDER BOTH SEISMIC AND TSUNAMI HAZARDS: A CASE STUDY OF THE ANTICIPATED NANKAI TROUGH EARTHQUAKE

In this paper, a framework for estimating the reliability of bridges and embankments under both seismic and tsunami hazards is proposed. Effect of ground motion induced-damage to structures on the deterioration of tsunami capacity is taken into consideration. Uncertainties associated with the hazard and fragility eval-uations are considered quantitatively. In an illustrative example, given the occurrence of the anticipated Nankai Trough earthquake, reliabilities of girder bridges, rigid frames and embankments among three cities are estimated and compared to identify which structure is more vulnerable and to know the location with the highest risk. Computational results demonstrate that the failure probability of structures under tsunami hazard with ground induced-damage is lower than that without ground-induced damage. The proposed method can provide a reliability-based retrofitting privatization for structures under multiple hazards.