A trial to verify flow control technology using a table-top hydraulic model at the Shingen Embankment on the Kamanashi River

Abstract

The Shingen Embankment built about 450 years ago by Takeda Shingen on the Fuji River and the Kamanashi River was designed to control flood flows in the Midai River (tributary) and the Kamanashi River by means of a series of flood control structures including Ishitsumidashi (stone masonry groins), Shougi-gashira (Japanese chess piece-shaped flow splitters), Hokkiri (dug channel), Juroku-ishi (sixteen large rocks used as energy dissipation works), Takaiwa (natural rock wall) and Kasumi-tei (discontinuous levees). The functions of these flood control structures have been subject to various interpretations, and some of those structures and their functions, such as the functions of a number of Shougi-gashira flow splitters and details on Juroku-ishi, which can only be guessed at today, are mysterious in many ways. This paper introduces an attempt at verifying the flow control technology made possible with these flood control structures by using a table-top hydraulic model developed with the aim of explaining the hydraulic phenomena involved.