RESILIENCE ASSESSMENT OF ROAD BRIDGES IN MULTI-HAZARD ENVIRONMENT

Abstract

Highway transportation networks play a vital role in today's economic and societal life and affect growth and employment. Hence, their undisrupted functionality and their quick recovery even after extreme natural hazard events are critical. To this end, resilience assessment of transportation networks against natural hazards is needed for decision-making processes in planning maintenance and retrofit actions, as well as for post-event risk management. This study aims to propose a multi-hazard resilience assessment framework for bridges that are the key components of transportation networks. The first step of the framework is the identification of critical hazards (i.e., earthquakes, floods) and the derivation of hazard curves and scenarios based on their probability of occurrence. The second step consists of a fragility assessment process based on computational analysis for single or multi-hazard occurrences given a range of hazard intensities. The third step includes the evaluation of functionality losses based on fragility assessment. In the fourth step, the required restoration time is estimated, and resilience metrics are calculated as dimensionless indicators. The proposed framework is applied to a case study riverine bridge, and comparative results on the single hazard and the multi-hazard resilience metrics are discussed. It has been observed that the effect of the consideration of multi-hazard scenarios is significant on the resilience of bridges.