| 摘要 |
PURPOSE:To vertically drive a mandrel as well as prevent the occurrence of buckling by penetrating plural mandrels through a guide part at given intervals. CONSTITUTION:When loosening a wire 5, a mandrel 6 is lowered under its own weight and by the weight of a guide part 12, and its lower end is thrust through a sand mat S and penetrated into the seabed B. The guide part 12 is lowered and reaches the upside of the sand mat S, penetrating pins 13 are thrust into the mat S, and the guide part 12 is fixed. The mandrel 6 is then driven into the ground B by a wire 10 and pulled up by pulling the wire 5 while a draining member D is left behind, whereupon a guide support 6a comes into contact with the downside of the guide part 12 and the guide part 12 is pulled out in the state of being lifted up. The draining member D is cut off. |
