邻近地铁基坑工程多次换撑技术研究与应用

Research and Application of Multiple Support Replacement Technology in Adjacent Subway Foundation Pit

杭州市某小学局部设1层地下室,基坑西侧为地铁4号线隧道,围护结构距离右线隧道最小仅6.90 m。为更好地保护地铁隧道,基坑西侧采用了“多次换撑技术”。有限元计算结果表明,相比于单次换撑,采用多次换撑技术的隧道沉降量和水平收敛分别减少22.41%和21.63%。多次换撑计算结果与监测结果较为接近,表明该技术有助于控制隧道变形,保证隧道安全。

A primary school in Hangzhou is partially equipped with a basement.The west side of the foundation pit is the subway line 4 tunnel.The minimum distance between the support structure and the right line tunnel is 6.90 m.In order to better protect the subway tunnel,the west side of the foundation pit adopts the"multiple support replacement technology".The results of finite element calculation show that when comparing with single support replacement,the settlement and horizontal convergence of tunnel with multiple support replacement technology are reduced by 22.41%and 21.63%,respectively.The calculation results of multiple support replacement are close to the monitoring results,which is helpful to control the tunnel deformation and ensure the tunnel safety.