Resilience Assessment of Shape Memory Alloy–Reinforced Concrete Coastal Bridges Subjected to Tsunami Loads

Abstract

The consequences of natural hazards like tsunamis often lead to severe damage to coastal bridges, resulting in socioeconomic loss, delays in rescue operations, and even loss of human lives. It is therefore important to quantify the vulnerability and improve the resilience of coastal bridges subjected to tsunami loading using advanced construction materials. This paper is the first-ever attempt to study the potential of the nickel–titanium shape memory alloy (Ni-Ti SMA) reinforcement in enhancing the resilience of reinforced concrete coastal bridges exposed to tsunami loads. The load modeled included drag, inertia, and slamming components. The impact of time-varying debris load associated with the tsunami waves was also analyzed. Under three representative wave periods, several combinations of wave heights were considered as the variable intensity measures for the fragility and resiliency assessments. The analysis results showed that the Ni-Ti SMA reinforcement in the plastic hinge region allows the piers to sustain higher drifts before significant damage compared to the conventional steel-reinforced piers. Moreover, the SMA-reinforced piers exhibited lower fragility and functionality loss under tsunami loads having wave periods greater than 5.50 s.