Agitation aerofoil and high tension injection combined use soil improvement construction method

摘要

PURPOSE:To prevent unimproved part of ground from being left between the improvement columns and between the improvement column and a construction by forming each solidifying agent discharge port at the lower edge of a rod and at the top edge of an excavating blade. CONSTITUTION:An excavating blade 22 is fixed in the vicinity of the top edge of a double pipe rod 21, and stirring blades 23 and 23 are fixed over the excavating blade 22, and a low pressure discharge port 24 having a pressure of 1-15kg/cm2 is formed at the top edge of the rod 21, and a high pressure discharge port 25 having a pressure of 50-300kg/cm2 is formed at the top edge of the excavating blade 22. The rod 21 is excavation-advanced in revolution in the ground, discharging a solidifying agent from the low pressure discharge port 24, and a center improvement column 26a is construction-executed. Then, the rod 21 is pulled up in revolution, discharging the solidifying agent from the high pressure discharge port 25, and an outside improvement column 26a is construction-executed. Then, the rod 21 is excavation-advanced in revolution again, and the outside diameter of the outside improvement column 26b is spread by discharging the solidifying agent from the high pressure discharge port 25.