盾构隧道下穿管道施工引起的管道水平位移研究

采用两段法研究了盾构隧道下穿管道施工引起的管道水平变形特性，在第1阶段改进了Loganathan公式，求得盾构隧道以任意角度下穿管道施工引起的管道轴线处土体水平位移，第2阶段采用Vlasov模型模拟管土相互作用，并求得管道水平位移解析解。通过与工程监测数据及有限元计算结果的对比，验证了方法的正确性，并进一步分析了管道与隧道夹角、管道直径以及隧道埋深对管道变形的影响。结果表明：盾构隧道斜下穿管道施工时，隧道与管道相交角度的大小对管道水平位移造成的影响显著，随着夹角的减小，管道的水平位移逐渐增加；当管道与隧道相交角度较小时，盾构隧道开挖引起的管道水平位移相对管道竖向沉降不可被忽略；随着管道直径的增大、隧道埋深的增加，盾构隧道斜交下穿管道施工引起的邻近管道变形均减弱。

Analysis of horizontal pipeline deformation caused by shield tunnelling

The two-stage method is used for analyzing the pipeline deformation caused by the underneath shield tunneling. In the first stage, the Loganathan formula is modified for studying the ground loss when the tunnel axis intersection with the pipeline axis is not orthogonal. The soil-pipeline interaction is studied based on the Vlasov model in the second stage, and the pipeline deformation is also obtained. Then, through comparison with the finite element results, the proposed method was verified to be correct. The influences of pipeline diameter; tunnel depth and intersection between the tunnel and pipeline on pipeline deformation have been further studied. The parametric study shows that the intersection angle of the tunnel and the pipeline significantly influences the pipeline horizontal displacement, and the pipeline deformation increases remarkably as the intersection angle decreasing. The parametric study indicates:a. the pipeline horizontal displacement can''t be ignored compared to the pipeline vertical displacement when the intersection angle of the tunnel and the pipeline is relatively small; b. the pipeline deformation is weakening as the pipeline diameter and tunnel depth increasing.