矩形顶管穿越敏感交通干线风险控制技术研究

Research on Risk Control Technology of Rectangular Pipe Jacking Crossing Sensitive Traffic Arteries

为探究过站井和接收井加固前后矩形顶管穿越敏感交通干线对地面沉降的影响,以望京西站1号换乘通道施工项目为研究对象,基于有限元软件分析项目在加固前后地面及交通干线沉降规律。结果表明:无加固条件下,在右线顶管顶进过程中,掌子面前方隆起土体影响范围为15 m;顶管施工对地面的影响以沉降为主,且在顶管顶进方向始发井处沉降量最大。加固条件下,顶管穿越交通干线时,路面最大沉降值相较于无加固条件减小3.5~5 mm;加固前后沿顶管顶进方向地面纵向沉降曲线均可分为隆起阶段、迅速沉降阶段和沉降稳定阶段;加固前后交通干线路面纵向沉降槽的影响范围均为2D(D为矩形顶管长边长度)。

In order to explore the influence of rectangular pipe jacking on the ground settlement when crossing the sensitive traffic trunk before and after the reinforcement of the station well and the receiving well,the construction project of No.1 transfer passage of Wangjing West Railway Station was taken as the research object,and the settlement law of the ground and traffic trunk before and after the reinforcement was analyzed based on the finite element software.The results show that the influence range of the uplifted soil in front of the tunnel face is 15 m when the right line pipe is jacked in without reinforcement.In the process of pipe jacking construction,subsidence is the main influence on the ground,and the subsidence is the largest in the direction of pipe jacking.Under the reinforced condition,the maximum settlement value of the road surface decreases by 3.5~5 mm compared to the non reinforced condition when the pipe jacking crosses the traffic trunk.The longitudinal settlement curve of the ground along the jacking direction before and after reinforcement can be divided into uplift stage,rapid settlement stage and stable settlement stage.The influence range of the longitudinal settling trough of the traffic trunk road surface before and after the reinforcement is 2D(D is the length of the long side of the rectangular pipe jacking).