| 摘要 |
PURPOSE:To simplify the drawing operation of an existing pile by a method in which the area outside an existing pile is concentrically excavated by an auger pipe, connecting pipes are orderly fitted with the periphery of the existing pile, and the existing pile is pulled out by using the chucker of the auger pipe. CONSTITUTION:An auger pipe 1 is matched with the center of an existing pile 31 and attached to a vertically movable rotary kelley bar 28 through a head pipe 25. Then, the kelley bar 28 is turned clockwise, the area outside the pile 31 is excavated by the spiral blade 1A of the pipe 1, connecting pipes 9 are attached between the pipes 25 and 1 to extend the pipes, and the pipes 1 and 9 are connected with the periphery of the existing pile 31 and buried. When the pile 1 reaches the lower end of the existing pile 31, the existing pile 31' is grasped by the chucker, the kelley bar 28 is turned counterclockwise to raise the existing pile, and the existing pile 31' is pulled out. |
