| 摘要 |
PURPOSE:To form large-diameter compacted sand pile by a method in which sand is charged into a casing provided with a tapered tube having an expanded lower part, and the casing is vertically moved while packing sand by a screw feeder. CONSTITUTION:Under a state a casing 1 being penetrated to a given depth into soft ground, a rotary shaft 5 is turned continuously, and sand 8 being charged is packed into tapered portion 4 by a screw feeder 6. Since the feeder 6 is continuously turned although the casing 1 is slightly raised and a space 9 is formed between the charged sand 8 and the tapered portion 4, the space 9 is soon packed with sand 8'. When the casing 1 is lowered, the sand in the tapered portion 4 is compacted, and the underpart sand is pushed out from the lower end. By repeating these processes to the upper part, a compacted sand pile of a larger diameter than the casing 1 can be formed. |
