Risk-Based Vulnerability Analysis of Deteriorating Coastal Bridges under Hurricanes Considering Deep Uncertainty of Climatic and Socioeconomic Changes

Abstract

Corrosion and hurricanes pose substantial risk to coastal bridges. This risk is compounded by future climatic and socioeconomic changes due to the increasing temperature and humidity, rising sea level, changing frequency and intensity of hurricanes, and amplifying exposure and consequences to adverse events. These future conditions, however, involve deep uncertainty, making life-cycle risk assessment and management extremely difficult. To address this challenge, a novel approach is proposed to identify, among various factors related to climatic and socioeconomic changes, the vulnerability of coastal bridges that could lead to unacceptable life-cycle risk. The considered factors include temperature increase, sea level rise, hurricane frequency and intensity, and socioeconomic growth. The acceptable risk is derived from the threshold reliability index of existing structures and the associated failure consequences. The entire space of relevant factors is divided into acceptable and unacceptable categories using Latin hypercube sampling and life-cycle risk assessment. Advanced analysis tools, including feature scoring, scenario discovery, and dimensional stacking, are then used to pinpoint the driving factors of bridge vulnerability and their thresholds that are prone to create unacceptable risk. The proposed approach is applied to a representative bridge in a coastal setting. The implication of the approach on robust decision-making about climate adaptation is also discussed.