UNDER REAMING AUGER APPARATUS AND UNDER REAMED PILE CONSTRUCTION METHOD USING THE SAME

摘要

The present invention can be drilled by expanding the diameter of the lower part of the drilling hole in the ground, and the auger wing is expanded by downward movement without separate mechanical manipulation and malfunction, and the auger wing can be recovered by folding the auger wing only by upward movement. It relates to an apparatus and a method for constructing an expansion pile using the same. According to the present invention, a connection portion formed on the upper end to be connected to the lower end of the excavation rod, an ogre wing receiving portion formed on the front surface of the lower end to receive the following auger wing, a hinge pin receiving hole for preventing the detachment of the hinge pin, and an inside an auger housing comprising a through hole formed as a passage for the movement of air and injection material to the auger housing, the outer diameter of which is less than or equal to the inner diameter of the perforated hole; An auger wing coupling portion fitted to the auger wing receiving portion of the auger housing, a hinge pin through hole through which a hinge pin for preventing separation from the auger housing passes, and an auger wing protrusion protruding out of the outer diameter of the auger housing a pair of ogre wings comprising; a hinge pin passing through the hinge pin through hole and coupled to the hinge pin receiving hole to prevent separation of the auger wing and the auger housing; and a plurality of auger tips provided on the front surface of the auger wing to crush the ground; including, when reaching the lower part of the drilling hole, rotate around the hinge pin to unfold a pair of auger wings, and the auger wing protrusion is perforated Expansion auger device is provided, characterized in that the hole is expanded outside the outer diameter, drilling the ground with an outer diameter wider than the outer diameter of the perforated drilling hole to form a drilling hole.