| 摘要 |
PURPOSE:To raise the top bearing force and circumferential frictional force of a pile by making up the pile having an upper part and a lower part each of which has a specific cross section. CONSTITUTION:A load link 2 is provided near the lower end 3 of an outer tube A coated or covered with a lubricant, and a load link 4 is provided near the lower end 5 of an inner tube B in such a way as to enable the tube B to move inside the tube A by means of the links 2 and 4. Also, a grout hole 6 is provided near the lower end 7 of the tube B, and a steel head 8 is welded to the lower end 7. The tube A is driven and fixed by a fixing tool 18, the tube B whose upper end is provided with a driving core shaft 14 serving as a grout tube is driven, concrete is poured into between the maximum diameter portion of the head 8 and the outside diameter portion of the tube B, the shaft 14 is pulled out, and the concrete (not illustrated) is poured into the tube A to form a pile. Thus, the circumferential friction force and the vertical bearing force can be raised for the lower part of the pile, and the horizontal yield strength can be raised for the upper part of the pile. |
