Structural Damage Under Multiple Hazards in Coastal Environments

Coastal structures are susceptible to a variety of natural hazards, such as wind, storm surge, waves, earthquakes, and tsunamis. These hazards must be fully studied and well understood in order to effectively and safely design and construct hazard-resilient structures. Knowledge of the damage mechanisms associated with coastal hazards helps reveal the anatomy of damage to constructed facilities during an event, which exposes vulnerabilities in current design practices. This paper focuses on damage to residential structures caused by hurricane winds, storm surge, and waves. After the different loading mechanisms associated with hurricanes are discussed, two case studies are introduced that examine structural damage during Hurricane Katrina (2005). On-site post-disaster field surveillance is complemented by the analysis of aerial photographs, satellite images, and data from wind and storm surge models in order to determine the structural damage timeline. The case studies demonstrate the importance of considering multiple hazards when designing and constructing coastal structures. A design and analysis framework that combines multi-hazard engineering strategies with performance-based design procedures is then introduced. The new approach seeks to significantly improve structural reliability in the most efficient and effective manner.