RECONSTRUCTION METHOD OF PILE FOUNDATION AND PILE FOUNDATION STRUCTURE

• Main Authors: HORII YOSHIHIRO, IIZUKA TAKAFUMI, KOMURO TSUTOMU, KANEDA KAZUHIRO
• Format: Patent
• Language: English; Japanese
• Published: 01.10.2015
• Subjects: EMBANKMENTS; EXCAVATIONS; FIXED CONSTRUCTIONS; FOUNDATIONS; HYDRAULIC ENGINEERING; SOIL SHIFTING; UNDERGROUND OR UNDERWATER STRUCTURES

PROBLEM TO BE SOLVED: To provide a construction method of a foundation structure which can easily construct a foundation structure supporting a superstructure in a base-isolated manner and having a pile head semi-rigid connection function, and a foundation structure.SOLUTION: A reconstruction method of a pile foundation includes: a pile driving step of arranging a plurality of temporary piles around an existing pile 20; an excavation step of forming a work pit by excavating around a pile head part of the existing pile 20; a pile cutting step of shifting application of the self weight of a superstructure so that the temporary piles receives the self weight and cutting the pile head part of the existing pile 20; and a base isolation step of inserting a base isolation device 30 between a foundation slab 11 and the existing pile 20 and forming a new pile head part 22 decreasing in a diameter upward, right under the base isolation device 30. A pile foundation structure is formed by the reconstruction method. 【課題】上部構造物を免震支持するとともに、杭頭半剛接合機能をも備えた基礎構造を簡易に構築することを可能とした基礎構造の構築方法および基礎構造を提案する。【解決手段】複数の仮設杭を既設杭２０の周囲に配置する杭打ち工程と、既設杭２０の杭頭部周辺を掘削して作業ピットを形成する掘削工程と、上部構造の自重を仮設杭に受け替えるとともに、既設杭の杭頭部を切断する杭切断工程と、基礎スラブ１１と既設杭２０との間に免震装置３０を挿入するとともに、上に向うに従って縮径する新設杭頭部２２を免震装置３０の直下に形成する免震化工程とを備える杭基礎の改築方法およびこれにより形成された杭基礎構造。【選択図】図１