Masashi Watanabe, T. Yoshii, V. Roeber, K. Goto, F. Imamura
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引用次数: 4
Abstract
Numerical computations for boulder transport have become a state-of-the-art tool for hindcasting the hydraulic processes associated with past storm wave and tsunami events. Since most previously developed two-dimensional formulations cater to boulders with symmetric outlines, they can consequently reproduce the transport distance and the velocity of boulders of cubic shape or similar structured geometries reasonably well. However, the formulations exhibit limitations when applied to rectangular- and flat-shaped boulders. The presently available formulations have difficulties reproducing the variations of frictional drag force due to the changes of the boulders’ contact time with the ground. We have developed an extended boulder transport formulation and derived a new empirical roughness coefficient by considering the shape of boulders that accounts for the changes of the boulders’ contact time with the ground. In comparison to other existing transport formulations, the present method provides superior accuracy of block velocity and transport distance in most cases — especially for boulders of rectangular geometry. Even by neglecting the full three-dimensional processes, numerical computations extended with the proposed boulder transport formulation can help explaining historic wave regimes, which were responsible for the transport of a variety of coastal boulders reported around the world.
期刊介绍:
Journal of Earthquake and Tsunami provides a common forum for scientists and engineers working in the areas of earthquakes and tsunamis to communicate and interact with one another and thereby enhance the opportunities for such cross-fertilization of ideas. The Journal publishes original papers pertaining to state-of-the-art research and development in Geological and Seismological Setting; Ground Motion, Site and Building Response; Tsunami Generation, Propagation, Damage and Mitigation, as well as Education and Risk Management following an earthquake or a tsunami.
We welcome papers in the following categories:
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Geotechnical hazards and response
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Material Behaviour
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Tsunami propagation: Physical oceanography
Run-up and damage: wave hydraulics.