| 摘要 |
PURPOSE:To raise the efficiency of pile striking operation by a method in which the penetration force of a pile is regulated according to the penetration resistance in such a way as to obtain an optimal penetration speed. CONSTITUTION:A vibrator 1 is hung down and supported on a winch device 14 to be driven by a proper driver 16 so that a pressing force to a pile 25 can be adjusted by winding-up or down the operation of the device 1. When the penetration speed of the pile 25 is lowered to less than a set speed, a target pile pressing force to recover the penetration speed of the pile 25 to more than a set penetration speed by a pressing force controller 30 composed of a pressing force control circuit 32, etc., is calculated, and the driver 16 is operated such that the present pressing force is matched with the target pressing force. For example, when the penetration speed of the pile 25 is lowered, the control valve 17 is operated by the circuit 32 to lower the rotation speed of an oil-pressure motor 16, and thereby the pressing force of the pile is reduced by a given value. Even when the penetration resistance of the pile is varied, the penetration speed of the pile 25 can thus be kept at more than set speed all the time. |
