Experimental Study on the Characteristics of River Tsunami

Abstract

In this study, tsunami run-up experimental model with a scale of 1 to 330 was set up in a tank with 33m length, 30m width and 0.5m height, which reproduces topography around Kitakami River 10 km long with Oppa bay. In the experiments, two types of tsunami were made by tsunami generator and influences of presence of river spit, highwater channel, riverbed roughness, presence of levee breach in some section to tsunami run-up. To recognize these influences, water levels in the river and land area, water volume going up through 10kilometer post of the river were measured during tsunami run-up. It was recognized that presence of river spit, decrease of riverbed roughness make distance of tsunami run-up longer and levee breach sometimes makes the distance shorter.

Tsunami Bores in Kitakami River

“…The Kitakami bathymetry data used in this work were collected by the Kitakamigawa-Karyu (Downstream region of Kitakami River) River Office, MLIT, and further processed in the National Institute for Land and Infrastructure Management (NILIM), Japan. The bed elevation in Kitakami was measured at the river's cross-sections at a 200-m interval along the river, and then interpolated onto a 10-m-resolution grid (Fukushima et al, 2013). Figure 8 shows the cross-river bed profiles next to the gauges, as well as the along-river bed and surface profiles.…”

Tsunami Bores in Kitakami River

“…The Kitakami bathymetry data used in this work were collected by the KitakamigawaKaryu (Downstream region of Kitakami River) River Office, MLIT, and further processed in the National Institute for Land and Infrastructure Management (NILIM), Japan. The bed elevation in Kitakami was measured at the river's cross-sections at a 200-m interval along the river, and then interpolated onto a 10-m-resolution grid (Fukushima et al, 2013). Figure 8 shows the cross-river bed profiles next to the gauges, as well as the along-river bed and surface profiles.…”