Vulnerability assessment of coastal bridges on Oahu impacted by storm surge and waves

Vulnerability assessment of four selected prototype coastal bridges on the island of Oahu, Hawaii, to the combination of storm surge and waves is presented. The maximum storm surge condition is estimated by considering an extensive series of simulated hurricanes making landfall on the island of Oahu, where the bridges are located. For the given extreme environmental conditions, wave loads on the deck of the selected bridges are calculated by use of several theoretical and computational approaches, including Euler’s equations (OpenFOAM), the Green–Naghdi nonlinear equations, linear long-wave approximation and existing simplified, design-type force equations. Multiple scenarios of the relative location of the bridge deck and the still-water level are studied to determine the maximum possible wave loads on the bridge decks. Vulnerability of the coastal bridges to storm wave loads is determined by comparing the capacity of the bridge to the wave-induced loads on the structure.