盾构施工引起横向沉降槽宽度分析

为了确定盾构施工的横向预加固范围以及监测范围,确保盾构施工安全,以北京地铁14号线为工程背景,对盾构施工引起的横向沉降槽宽度进行了分析。提出了横向预加固范围以及监测范围,提出了一种计算方法;并在此基础上,确定适用于北京地层,横向沉降槽宽度与其系数的相关关系。研究结果表明:主要沉降应发生于距隧道轴线水平距离为2i范围内,i为沉降槽宽度系数,次要影响区域为2i~3i范围内;应用新方法计算盾构隧道施工横向沉降槽宽度为距隧道轴线水平距离约为1 h或2 D,h为隧道埋深,D为隧道直径;确定沉降槽宽度与沉降槽宽度系数之间的关系为2.5倍较3倍更为合理。

Analysis of Width of Traverse Settlement Trough Caused by TBM Construction

To clarify the lateral range of pre-reinforcement and monitoring range, ensure the safety of TBM construction, this paper based on the project that Beijing subway line14, analyzed the width of transverse settlement trough caused by TBM construction. It made sure the lateral range of pre-reinforcement and monitoring range, presented a calculation method, and on this basis, determined the correlation between the width of transverse settlement trough and its coefficients. The result showed that: the main range of settlement is the horizontal distance from the axis of the tunnel within the scope 2i, i is the width coefficient of settlement, the secondary range is the distance within the region 2i-3i; the transverse width of settlement trough caused by TBM construction is the horizontal distance from the axis of the tunnel within the scope 1h or 2D, h is the tunnel depth, D is the diameter of the tunnel; the relationship between the width of transverse settlement trough and its coefficients is 2.5 times, it is better than 3 times.