| 摘要 |
PURPOSE:To permit an exisiting pile to be pulled out with a small drawing force by a method in which a casing is penetrated into the surrounding ground of the existing pile, a coupler having expansible check claws is inserted into the pile, the claws are expanded and coupled with the inside of the pile, and then the coupler is pulled out. CONSTITUTION:A casing 2 set around an exisitng pile 1, a coupler 4 having check claws 3 expansible by pressure oil, etc., is inserted into the pile 1, and the check claws 3 are expanded and coupled with the inside of the pile 1. Then, the coupler 4 is pulled up, or where an intermediate pile or a lower pile 1a is present, the coupler 4 is again inserted into the lower pile 1a and the likewise pulled up to draw up the pile 1, and lastly the casing 2 is pulled out. The pile can be pulled out under a condition that the friction around the pile 1 is excluded. |
