遡上津波による陸上構造物周辺の局所洗掘に関する研究

抄録

The 2004 Indian Ocean tsunami caused large-scale sediment transport, resulting in substantial scour around a huge number of structures. In this study, tsunami-induced local scour around a land-based structure with a rectangular cross-section on a sand foundation was investigated with a series of hydraulic model experiments and numerical simulations. It was, as a result, revealed that local scour around the seaward corner of the structure could be evaluated with not only flow velocities on the sand foundation but effective stresses near the surface of the sand substrate, that is, flow velocities with a large Shields number resulted in a scour hole around the seaward corner of the structure during restricting force between sand particles fell down due to a decrease in effective stresses inside the sand substrate.