| 摘要 |
PURPOSE:To absorb the falling energy and impact sound of overflow water by a method in which a subsidiary rubber bag whose sectional area becomes smaller than the main rubber bag when expanded is integrally provided in parallel sidewardly on the downstream side of the main rubber bag of a rubber dam in such a way as to keep the sufficient height of the dam. CONSTITUTION:A subsidiary rubber bag 11 whose sectional area becomes smaller than the main rubber bag 10 when expanded is integrally provided in parallel sidewardly on the downstream side of the main rubber bag 10 of a rubber dam 1, and the rubber bags 10 and 11 are connected with each other through their communication holes. When the main rubber bag 10 is expanded, the rubber bag 11 is also expanded concurrently through its communication hole. In this case, since the bottom of the downstream side of the main rubber bag 10 is sidewardly supported by the subsidiary rubber bag 11 expanded, its flat deformation can be prevented even when pressed under water pressure in the direction of arrow X, and thereby sufficient height of the dam can be kept. Overflow water W passing over the upside of the main rubber bag 10 collides with the rubber bag 11, and its falling energy and impact sound can be absorbed. |
