METHOD FOR CONSTRUCTING A FOOTING AT THE BOTTOM OF A PILE AND A FIXED ANCHORAGE PORTION OF A TENSION MEMBER, AND TOOL FOR EXPANDING A BOREHOLE WALL FOR SAME

摘要

The present invention relates to a method for constructing a footing at the bottom of a pile and a fixed anchorage portion of a tension member, in which: a vertical hole is bored into the ground, and then a tool for expanding the borehole wall is disposed within the bottom of the hole; the tool is driven to expand the bottom of the hole and form an expanded portion, and simultaneously, a portion of the ground on the upper side of the expanded portion is supported by means of the tool; concrete for a footing or a fixed anchorage portion is passed through the tool to fill the expanded portion of the hole with the concrete; and the tool is gradually contracted to form a space that is filled with the concrete, thereby finally casting the concrete into the footing or the fixed anchorage portion at the bottom of the pile.