Journal of Earthquake and Tsunami

During tsunami action on a structure, the structure is subjected to heavy loads with complex phenomena which include the interactions among tsunami, structure and air. In order to mitigate tsunami damages on structures, it is important to understand the characteristics of tsunami hydraulic loads acting on the structures with taking into account the above interactions. In the present study, the characteristics of tsunami forces on a building structure are investigated using a two-phase flow model. Two types of building models, a building without openings and with openings, were dealt with; and the effects of openings on the building under the tsunami hydraulic loads are examined. The simulation results were compared with the results obtained from one-phase flow simulation, and also verified with experimental data. The numerical results show good agreement with the measured ones. Furthermore, the effects of air taken into the flow and opening configuration on the characteristics of pressures and uplift forces were also discussed.

Both lithologic and topographic irregularities may trigger significant scattering phenomenon of seismic waves. In this study, a series solution is presented for the analysis of scattering of SH waves induced by a trapezoidal valley during earthquakes. An appropriate region matching technique is utilized to divide the physical region into four computational subregions. The wave motions of each subregion are obtained as an infinite series of wave functions with unknown coefficients in the respective cylindrical coordinates through wave function expansion method. The Graf's addition theorem is applied to transform the wave potentials of each subregion into the global coordinate. The mixed boundary conditions are solved by truncating the obtained infinite equations into a finite set. The effects of geometrical topographies and sedimentary properties on the amplification are analyzed and discussed in terms of steady-state and transient response analysis.

The accuracy of the risk evaluation associated with existing dams as well as the efficient design of future dams is highly dependent on a proper understanding of their behavior due to earthquakes. This paper presents a 3D anisotropic damage model for arch dam under strong earthquakes. The modified effective Mohr–Coulomb criterion is adopted as the failure criteria of the dynamic damage evolution of concrete. From the simulation of the dynamic damage process, some process fields of the dynamic displacement, the dynamic stress, dynamic damage distribution and other necessary information for the safety evaluation are obtained. These results show that the seismic behavior of concrete dams can be satisfactorily predicted. This will provide a reasonable theoretical support on the safety evaluation of the capability for concrete arch dams against earthquake loading.