EXPERIMENTAL STUDY ON BOTTOM TOPOGRAPHY CHANGE IN HARBOR DUE TO TSUNAMI

Tsutomu Sakakiyama, Masafumi Matsuyama, Takumi Yoshii

Abstract


Bottom topography change due to tsunami was experimentally investigated using a rectangular harbor model in a 2-D wave flume. Water surface level and velocity field were obtained as well to discuss the external forces. Accumulation region was observed in the middle of the harbor inside. Formed was conical bed topography. Erosion was around the accumulated region and at the breakwater head as local scour. These topography changes were caused by the tsunami-induced vortices inside the harbor and at the breakwater head.

Keywords


tsunami; sand transport; topography change; vortex; water elevation level; velocity field

References


Andersen, A., B. Lautrup, and T. Bohr. 2003. An averaged method for nonlinear laminar Ekman layers, Journal of Fluid Mechanics, 487, 81-90. http://dx.doi.org/10.1017/S0022112003004658

Fujii, N., M. Ohmori, M. Takao, S. Kanayama, and H. Ohtani. 1993. On the Deformation of the Sea Bottom Topography due to Tsunami, Proceedings of Coastal Engineering, JSCE, 45, 376-380(in Japanese).

Fujita, N., K. Inagaki, N. Fujii, M. Takao, and T. Kaneto. 2010. Study on field application of estimation model for topography change due to tsunamis, Annual Journal of Civil Engineering I the Ocean, JSCE, 26, 213-218(in Japanese).

Mizuguchi, M. 1991. Method of resolving incident and reflected waves in shallow water, Proceedings of Coastal Engineering, JSCE, 38, 31-35(in Japanese).http://dx.doi.org/10.2208/proce1989.38.31

Kihara, N., and M. Matsuyama. 2010a. Three-dimensional hydrostatic numerical simulations on tsunamiinduced sediment transport in a model harbor, Abstracts of the 3rd International Tsunami Field Symposium, 31-32.

Kihara, N., and M. Matsuyama. 2010b. Numerical simulations of sediment transport induced by the 2004 Indian Ocean tsunami near the Kirinda port in Sri-Lanka Proceedings of the 30th International Conference on Coastal Engineering. (in press)

Rubey, W.W. 1933. Settling velocities of gravels, sand and silt particles, American Journal of Science, 25, 325-338. http://dx.doi.org/10.2475/ajs.s5-25.148.325

Soulsby, R. 1998. Dynamics of marine sands, Thomas Telford, 270p. PMCid:1343172http://dx.doi.org/10.1680/doms.25844

Takahashi, T., N. Shuto, F. Imamura, and D. Asai. 2000. Modelling sediment transport due to tsunamis with exchange rate between bed load layer and suspended load layer, Proceedings of International Conference on Coastal Engineering, 2, ASCE, 1508-1519.

Yoshii, T., M. Ikeno, and M. Matsuyama. 2009. Experimental study of sediment transport caused by tsunami, Proceedings of Coastal Dynamics 2009, Paper No. 32.

Yoshii, T., M. Ikeno, M. Matsuyama, and N. Fujii. 2010. Pick-up rate of suspended sand due to tsunami, Proceedings of the 30th International Conference on Coastal Engineering. (in press)


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