CONSTRUCTION METHOD FOR LIQUEFACTION COUNTERMEASURE STRUCTURE USING EARTH RETENTION WALL

To provide a construction method for a liquefaction countermeasure structure using an earth retention wall, which carries out efficient construction of a connection part between an outer periphery retention wall 2 where a reinforcement steel member 3 as a core member is installed and a wall-shaped ground improvement body 4 constructed inside thereof, while enhancing the strength continuity and integration of the connection part.SOLUTION: A construction method for a liquefaction countermeasure structure comprising an outer periphery retention wall 2 as a continuous underground wall where a reinforcement steel member 3 as a core member is installed in a soil-cement column row wall and a wall-shaped ground improvement body 4 partitioning the inside of the outer periphery retention wall 2 to a plurality of partitions constructs an auxiliary column row wall part 6 made of soil cement so as to overlap with a column row of the outer periphery retention wall 2 at a connection part between an inner peripheral surface of the outer periphery retention wall 2 and an end part of the wall-shaped ground improvement body 4. The end part of the wall-shaped ground improvement body 4 is constructed so as to overlap with the auxiliary column row wall part 6.SELECTED DRAWING: Figure 3 【課題】山留壁を利用した液状化対策工の施工において、芯材としての補強鋼材３を建て込んだ外周山留壁２と、その内側に施工される壁状地盤改良体４との接続部の施工を効率的に行い、かつ接続部の強度的な連続性および一体性を高める。【解決手段】ソイルセメント柱列壁に芯材としての補強鋼材３が建て込まれる連続地中壁としての外周山留壁２と、外周山留壁２の内部を複数の区画に仕切る壁状地盤改良体４とからなる液状化対策工の施工において、外周山留壁２の内周面と壁状地盤改良体４の端部との接続部に、外周山留壁２の柱列とオーバーラップするようにソイルセメントによる補助柱列壁部４を造成する。この補助柱列壁部４に対し、壁状地盤改良体４の端部がオーバーラップするように施工する。【選択図】図３