| 摘要 |
PURPOSE:To completely fill up a space by increasing the volume of a back-filling grout injected into the space by adding an expandable compound small granule covered with a water-soluble substance to the back-filling grout. CONSTITUTION:Before or while adjusting a back-filling grout, expandable compound small granule covered with a water-soluble substance is added to the grout, and the grout is injected into spaces under the ground. Whereupon, by water content of the back-filling grout, the water-soluble substance is gradually dissolved, the expandable compound begins to effervesce in the presence of moisture before the grout is hardened, and the volume of the grout is increased to completely fill the spaces with the grout. As a water-soluble substance to be used for covering the expandable compound, one or two or more of polyvinyl alcohol, polyethylene oxide, gelatin, etc., are used. |
