地表超载对地铁盾构隧道的影响分析

针对地表超载导致的隧道竖向土压力问题，参照室内模型试验的隧道结构变形与土压力实测结果，建立了有限元模型。在地表超载作用下，分析了隧道穿越土层与隧道上覆土层的压缩性能对隧道周围土压力与结构变形的影响。结果表明：隧道穿越土层的压缩模量越小，地表超载作用导致的隧道竖向土压力越大，且对应的隧道水平土压力越小，隧道结构越容易发生横椭圆变形；隧道上覆土层的压缩模量越小，地表超载作用导致的竖向土压力越小，隧道结构发生的变形也越小；在软土地区地表堆土（超载）导致的隧道竖向土压力要大于按土柱理论计算所得的隧道竖向土压力。研究结果可为软土地区地铁盾构隧道设计与运营期管控提供参考依据。

Analysis of influence of surface surcharge on subway shield tunnel under

To investigate tunnel vertical earth pressure caused by surface surcharge, a finite element model is established based on the measured results of tunnel structure deformation and earth pressure of indoor model test. The developed model is used to analyze the influence of the compressibility of soil layers acrossed by tunnel and soil layers overlaying on tunnel on tunnel structure deformation and surrounding soil pressure under surface surcharge. The results show, the compressibility of soil acrossed by tunnel is smaller, the vertical earth pressure on the tunnel caused by surface surcharge is greater, the corresponding tunnel lateral earth pressure is smaller, which is more likely to cause lateral elliptical deformation in the tunnel structure. The lower the compressibility of tunnel overlaying soil is, the lower the surface surcharge-induced vertical earth pressure on the tunnel is, the smaller the deformation of tunnel structure is. The vertical earth pressure of the tunnel caused by surface pile soil(surcharge) is greater than that calculated by the theory of soil column. Thesis results can provide some references for the design and operational phase control of subway shield tunnel in soft clay.