| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a ground reinforcing method capable of being executed with little surplus earth, easily securing stable quality and being implemented at a low cost.SOLUTION: A tip drilling blade 2 engaged with a tip of a casing 1 blocks the tip of the casing 1 and has a plate-like blade and a vane section. The tip drilling blade 2 is: engaged with the casing 1 in a manner that rotates along with the casing 1 in a direction that the same rotates while being penetrated; and detached from the casing 1 when the same inversely rotates while being pulled out. A small-diameter concrete pile is constructed by: installing the casing 1 at a predetermined depth by rotating and pressing the same into the ground; placing an injection material 7 such as concrete inside the casing 1 without installing reinforcement; and pulling out the casing 1 before the injection material solidifies. The tip drilling blade 2 detached from the tip of the casing is left at a bottom of a borehole. Because excavated earth is consolidated when pressed against a wall surface of the borehole at an outer periphery of the casing 1, the small-diameter concrete pile can be constructed with little surplus earth. Also because the injection material is placed inside the casing where a diameter of the borehole is secured, the small-diameter concrete pile can be constructed with stable quality.</p> |
