An Integrated Approach for Numerical Simulation of Earthquake Generated Tsunamis: Modeling Tsunami Generation, Propagation, Inundation and Fragility Analysis of Coastal Structures

The present paper presents an integrated computational approach for earthquake generated tsunami prediction. The computational framework fully integrates the earthquake generated tsunami source, open-sea wave propagation, and wave run-up with inundation and on-shore effects. In addition, preliminary fragility analyses are presented considering the dynamic inelastic (damage) response of simple structures from both hydrostatic and hydrodynamic pressures. A simplified source model is developed based on pertinent local geologic and tectonic processes, observed seismic data, and measured seafloor and land deformations. The source model establishes estimates of the configurations of seafloor deformation that are used for the initial waveform in the tsunami simulations. Well-resolved bathymetric and topographic data are used to generate the computational grid. The FUNWAVE-TVD solver with the nonlinear Boussinesq form of the Navier-Stokes equations is used to numerically simulate tsunami wave propagation and inundation. The coastal impact from the tsunami is represented through the structure fragility curve. The developed integrated approach was used to simulate the 2011 Tohoku-Oki tsunami. The tsunami fragility curve presented in this paper predicts the failure fraction (or probability of failure) as a function of wave amplitude and accounts for the water impact velocity, wave height, and dynamic load history associated with the impacting wave.