Site Specific Wave Parameters for Texas Coastal Bridges: Final Report (0-6063-1)

There are about 20 coastal bridges located in hurricane evacuation routes in the State of Texas that are vulnerable to hurricane surge and wave action. Damage to these bridges could hamper emergency response and other services, and also cause tremendous economic loss. In recent devastating hurricane seasons of 2004, 2005, and 2008, several coastal highway bridges along the US coast of Gulf of Mexico suffered severe structural damages. To prevent structural failure of coastal bridges, the magnitude of wave load on coastal bridges must be determined. The objective of this research is to determine site-specific design wave parameters (i.e., wave height and wave period) that are needed in computation of wave loads and evaluation of wave effects on coastal bridges. In this project, we determined storm surge and wave parameters for four bridges using numerical models ADCIRC and SWAN. Simulation of water level including storm surge were performed with program ADCIRC, which also provides input to wave simulation. Wave parameters were determined by statistical analysis on simulation results performed with wave model SWAN at different storm surge and wind speed levels. Both wave and water level/storm surge simulations were vigorously validated with observed wave and water level data. The results of this research project will enable TxDOT to quickly implement the design methodology produced by an AASHTO/FHWA pooled fund study.