| 摘要 |
PURPOSE:To construct a culvert easily at low cost as well as raise its draining effect by covering a drain pipe with pumice stones as inorganic water-permeable materials (e.g., coal cinder, or volcanic rocks). CONSTITUTION:A construction machine is dragged by a bulldozer 4, soil 6 is excavated in a V-form by the plow 5 of the construction machine, and a plastic drain pipe 1 rolled annularly is buried under the soil. At the same time, pumice stones 2 stored in a hopper 3 are dropped to over the surrounding of the drain pipe 1. As the pumice stones 2, an inorganic water-permeable material, e.g., volcanic rocks, or coal cinder, is used. |
