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Fragility functions, as new measures for estimating structural damage and casualties due to tsunami attack, are developed by an integrated approach using numerical modeling of tsunami inundation and GIS analysis of post-tsunami survey data of the 2004 Sumatra–Andaman earthquake tsunami disaster, obtained from Banda Aceh, Indonesia. The fragility functions are expressed as the damage probabilities of structures or death ratio with regard to the hydrodynamic features of tsunami inundation flow, such as inundation depth, current velocity and hydrodynamic force. They lead to the new understandings of the relationship between local vulnerability and tsunami hazard in a quantitative manner.

In the 2011 Tohoku Earthquake, many structures were destroyed by the tsunami whose magnitudes were much larger than the design level. Tsunami defense structures in coastal areas will need reinforcement in the future, and for that reason it is important to evaluate tsunami behavior and resulting tsunami force. This study analyzes tsunami transformation around a Haramachi thermal power station which suffered serious damage by the tsunami due to the 2011 Tohoku Earthquake and which has complex topography and building layout. A three-dimensional (3D) tsunami simulation is carried out for a surrounding region of the Haramachi thermal power station using boundary conditions of the water surface elevation and flow velocity obtained from a two-dimensional (2D) tsunami simulation by a nonlinear shallow water model. Using these boundary conditions, the computer fluid dynamic model FLUENT is employed to simulate the tsunami behavior around the Haramachi thermal power station. The validity of the predictions is examined by comparison with actual traces of tsunami inundation depths (I.D.).

Taught by the lesson from the 2011 Tōhoku earthquake and tsunami, we aim to probe into the potential large-scale trench-typed tsunami threats to Taiwan by means of the deterministic method. In this paper, 18 trench-typed tsunami sources and the 4 fault-typed tsunami sources will be constructed. The detailed construction, including the rupture length and width, the scale of seismic moment, the slip as well as the dip angle, will be elaborated. The tsunami numerical model, COMCOT, will be applied to simulate tsunami propagation, run-up and inundation; multi-nested grids will be used for a complete simulation of the process of a tsunami from the beginning to the inundation. The simulation result shows that tsunami source from the northern segment of the Manila Trench will pose a serious threat to the safety of Taiwan's southwest coast. The tsunami energy from the Yap Trench can be substantially projected onto Taiwan, and threatens the coasts of northern, eastern, southern, as well as south-western Taiwan. The tsunami source from off the coast of Hualien will have a greater influence on the east coast of Taiwan.

In 2011, the tsunami generated by the Great East Japan Earthquake devastated infrastructure along the Pacific coast of northeastern Japan. In particular, the collapse of bridges resulted in much disruption to traffic, which led to delays in recovery after the disaster. We are developing a multi-scale and multi-physics tsunami disaster simulation tool to evaluate the safety and damage of infrastructure from huge tsunami. Multistage zooming tsunami analysis is one of the possible methods for implementing a high-resolution three-dimensional (3D) tsunami inundation simulation for a city. In this research, a virtual wave source that includes transition layers is proposed for a coupled simulation based on 3D particle simulation. The zooming analysis has been undertaken using the same particle method and a two-dimensional (2D) finite difference simulation. The 3D particle coupled simulation has been examined and validated.

This paper presents the details of a mass evacuation simulator with complex autonomous agents on a high resolution model of environment along with demonstrative applications that highlight its usefulness, need and uniqueness. Most of existing mass evacuation simulators are based on simplified models, and the use of complex models is limited to small scale simulations. This simulator makes use of high performance computing to introduce a complex agent system to simulate evacuations in hundreds of square kilometer size domains. The framework of the developed multi-agent system and some of the agents’ constituent functions for interacting with high resolution grid are briefly explained. Interactions are validated using field observations. Two sets of applications are presented to demonstrate the systems use for simulating mixed mode evacuation and evacuation in dynamically changing environment.

Many beaches in Penang island were severely inundated by the 26 December 2004 Indian Ocean mega tsunami with 57 deaths recorded. It is anticipated that the next big tsunami will cause even more damages to beaches in Penang. Hence, developing community resilience against the risks of the next tsunami is essential. Resilience entails many interlinked components, beginning with a good understanding of the inundation scenarios critical to community evacuation and resilience preparation. Inundation scenarios are developed from tsunami simulations involving all three phases of tsunami generation, propagation and run-up. Accurate and high-resolution bathymetric–topographic maps are essential for simulations of tsunami wave inundation along beaches. Bathymetric maps contain information on the depths of landforms below sea level while topographic maps reveal the elevation of landforms above sea level. Bathymetric and topographic datasets for Malaysia are, however, currently not integrated and are available separately and in different formats, not suitable for inundation simulations. Bathymetric data are controlled by the National Hydrographic Centre (NHC) of the Royal Malaysian Navy while topographic data are serviced by the Department of Survey and Mapping Malaysia (JUPEM). It is highly desirable to have seamless integration of high-resolution bathymetric and topographic data for tsunami simulations and for other scientific studies. In this paper, we develop a robust method for integrating the NHC bathymetric and JUPEM topographic data into a regularly-spaced grid system essential for tsunami simulation. A primary objective of this paper is to develop the best Digital Elevation and Bathymetry Model (DEBM) for Penang based upon the most suitable and accurate interpolation method for integrating bathymetric and topographic data with minimal interpolation errors. We analyze four commonly used interpolation methods for generating gridded topographic and bathymetric surfaces, namely (i) Kriging, (ii) Multiquadric (MQ), (iii) Thin Plate Spline (TPS) and (iv) Inverse Distance to Power (IDP). The study illustrated that the Kriging interpolation method produces an integrated bathymetric and topographic surface that best approximates the admiralty nautical chart of Penang essential for tsunami run-up and inundation simulations. Tsunami inundation scenarios critical to risk analysis and mitigation could then be developed using this DEBM for various earthquake scenarios, as presented in this paper for the 2004 Indian Ocean Tsunami.