| 摘要 |
PURPOSE:To cut down the cost of construction by a method in which a casing shorter than the length of ground to be improved is penetrated into soft ground, water and sand are supplied into the casing, and the casing is pulled up while regulating the pressure of air in the casing. CONSTITUTION:A casing 1, whose upper end is closed and the axial length is made shorter than the length of ground to be improved, is penetrated to a given depth into soft ground by a penetrator 3 through a power transmitter lever 2. Sand with water is supplied through a supply pipe 6 into the casing 1, and while controlling a pressure regulating valve inserted into a discharge pipe 7, the casing 1 is pulled up to form a given diameter sand pile. Used compressed air is recovered through the discharge pipe 7. |
