Underground structure and method of rebuilding building with underground building

摘要

PROBLEM TO BE SOLVED: To make a cast-in-place concrete pile larger in diameter and lower in cost when suppressing floating of an existing pressure board and occurrence of a board swelling phenomenon by installing the cast-in-place concrete pile for reconstruction of a building having an underground skeleton.SOLUTION: There is provided an underground structure 10 for reconstruction of a building having an underground skeleton, the underground structure including: an existing pressure board 22 which is not disassembled and left under the ground; a newly constructed cast-in-place concrete pile 40 constructed so as to penetrate the existing pressure board 22; a diameter-increased part 40A constructed on the existing pressure board 22 in the same body with a head part of the newly-constructed cast-in-place concrete pile 40, and having a larger diameter than through holes of the newly constructed cast-in-place concrete pile 40 and existing pressure board 22; and a cylindrical body 30 constructed on the existing pressure board 22 with a concrete wall while surrounding the diameter-increased part 40A so as to extend to above the ground water level.