| 摘要 |
PURPOSE:To prevent the occurrence of noise and vibration as well as secure the safety of operations by a method in which an expandible part attached with a blade is expanded or contracted in concrete by application of pressures. CONSTITUTION:An expandible part 4 with a superhard blade 5 is attached to reinforcing bars 3, and ready-mixed concrete is placed to form a foundation pile 2. A pressing machine 7 is operated to supply a pressure fluid through a hose 6 into the concrete, whereupon the part 4 is expanded and the blade 5 is cut into the concrete to break the concrete. |
