| 摘要 |
PURPOSE:To permit the automatic rising of a rising and falling dam without the need for manual operation by providing the intake port of a water supply pipe through which natural water of river is supplied at a preset level inside a baggy film of more than a given internal pressure. CONSTITUTION:The intake port 13b of a water supply pipe 13a through which natural river water is supplied into the flexible baggy film 11 is provided at a preset level at a given internal pressure in the baggy film 11, i.e., in such a way that a head from the basal face of the river bed 12 is formed. A valve 13e is provided on the drain port 13d side of a drain pipe 13c, and the drain port 14a of a spillway pipe 14 is provided at a place of more than a given internal pressure H. The baggy film 11 is raised by expansion by directing the upper flowing water of the dam from the intake port 13b through the water supply pipe 13a into the baggy film 11. Since the water coming from the intake port 13b after rising the baggy film 11 is discharged from the drain port 14a, freezing in the winter season can be prevented. |
