Laboratory and Numerical Simulation of Tsunami Inundation in a Coastal Urban Area

In recent years tsunamis have been recognized as one of the most catastrophic natural disasters in the world, highlighted by the 2004 Indian Ocean tsunami and the 2011 Tohoku earthquake and tsunami. However, both physical and numerical studies on tsunami wave inundation impact on a coastal urban area remain limited. For example, laboratory experiments on tsunami interaction with multiple coastal structures are relatively few, and numerical studies are more focused on the bare-earth conditions rather than the coastal urban topography. The objective of this dissertation is to study the influence of coastal structures on the tsunami wave inundation and loading within an urban area both numerically and physically. Two separate laboratory experiments were conducted to evaluate the numerical model performance within a coastal urban topography, as well as to collect data on the tsunami wave loading within a structural array sheltered by a partial wall. Another numerical simulation was performed to study the tsunami inundation and flow velocity within a structural array sheltered by a partially standing seawall. Results from the laboratory and numerical simulations on the coastal urban topography suggest that tsunami inundation and flow velocity can be significantly impacted by the arrangement of nearby coastal structures, and variation in results exists among different numerical models. The physical and numerical studies on the structural array sheltered by a partial wall demonstrate the sheltering effect among structures as the clearance and sheltering angle by another structure can largely affect the wave loading, inundation, and flow velocity at a certain location. Results from this dissertation provide better understanding on the tsunami behavior within a coastal urban area with dense structures and offer insights on how to improve the numerical simulations as well as disaster planning within a coastal urban area.