地铁运营隧道上方共线基坑的竖井联合门式抗浮框架施工方案研究

Research on Construction Scheme of Shaft Combined Portal Anti-floating Frame for Collinear Foundation Pit above Subway Operating Tunnel

地铁运营隧道上方开挖长距离共线基坑时,会造成隧道上方大面积卸载,易引起隧道结构上浮隆起。为应对隧道结构上浮隆起,文章基于理论分析,结合深圳市某新建道路与已建地铁运营隧道共线工程,分析地铁运营隧道上方共线基坑施工方案。根据工程具体情况,文章提出竖井联合门式抗浮框架施工方案,分析竖井联合门式抗浮框架施工参数与施工要点;然后对基坑施工时的隧道变形进行实测分析,得出竖井联合门式抗浮框架施工方案能有效控制隧道的上浮隆起,将基坑开挖对隧道结构变形的影响程度降到最低,该施工方案值得推广应用。

When excavating a long-distance collinear foundation pit above a subway operating tunnel, it will cause a large area of unloading above the tunnel, which will easily cause the uplift on the tunnel structure. Therefore, in order to cope with the uplift of the tunnel structure, based on the theoretical analysis, this paper analyzes the construction scheme of collinear foundation pit above the subway operating tunnel in combination with a new road and the existing subway operating tunnel collinear engineering in Shenzhen.According to the specific engineering situation, it puts forward the construction scheme of shaft combined portal anti-floating frame, and analyzes the construction parameters and construction points of shaft combined portal anti-floating frame. Then, the tunnel deformation during foundation pit construction is measured and analyzed. It is concluded that the construction scheme of shaft combined portal anti-floating frame can effectively control the floating uplift of the tunnel, and minimize the influence of foundation pit excavation on the deformation of the tunnel structure. The construction scheme is worthy of popularization and application.