浅覆土多盾构平行始发施工技术

Parallel Initiation Construction Technology of Multi-shield Tunneling in Shallow Soil

环球影城站是北京地铁八通线南延和7号线东延的环球影城站—施园站两个盾构区的共用始发站,为地面车站。因两区间盾构施工贯通节点相同,造成4线隧道盾构需在浅覆土、大坡度条件下平行始发。为确保施工安全,对施工过程进行数值模拟分析,从4台盾构机的施工顺序、始发前后间隔距离、地面荷载压力等方面分析对地面沉降的影响。按最优模拟结果,结合现场实际情况,采取合理的盾构掘进参数、径向注浆、地面覆压等辅助措施,对此条件下多盾构始发技术进行研究,在控制地层变形沉降等方面取得良好的施工效果。

Universal Studios Station is the common departure station of the two shield tunnels of Universal Studios Station—Shiyuan Station on the southern extension of Batong line and the east extension of line 7 of Beijing Subway, and it is a ground station. The perforation nodes of the shield construction are the same, which causes the shield of the four-lane tunnel to start in parallel under the condition of shallow covering soil and large slope. In order to ensure the construction safety, the construction process is numerically simulated and analyzed, and the impact on ground settlement is analyzed from the construction sequence of the 4 shield machines, the separation distance before and after the launch, and the ground load pressure. According to the optimal simulation results, combined with the actual situation of the site, reasonable auxiliary measures such as shield tunneling parameters, radial grouting, and ground overburden are adopted.The multi-shield launching technology under this condition is researched and verified, and good construction results are achieved in terms of controlling stratum deformation and settlement.