COMPACTION WORK OF BACK-FILLED SOIL AFTER UNDERGROUND PIPING WORK

摘要

PURPOSE:To prevent the subsidence of the ground surface by sufficient compaction by a method in which back-filled soil around an underground pipe layed in a trench is compacted by a legged hammer, and the upper part of the trench is back-filled with soil and compacted by the strike of a flat-plate hammer. CONSTITUTION:A legged hammer 1 is set in such a way as to position its legs 1b on both sides of an underground pipe 2, and a vibro-hammer 3 is set on the hammer 1. The surrounding of the pipe 2 is back-filled with soil E through the hammer 1 and the soil E is compacted to a stable ground by application of vibration. The remaining soil E is back-filled to near the ground surface, and a flat-plate hammer 4 is repeatedly dropped to compact the soil E by the strike of the hammer 4. The surrounding soil portion of the underground pipe 2 can thus be sufficiently compacted to prevent the subsidence of the ground surface.