重叠地铁隧道地表沉降数值分析

Numerical analysis of ground settlement of overlapping subway tunnel

利用数值分析法,建立重叠隧道不同埋置深度、空间角度及水平间距多组数值模型,从地表沉降展开研究。结果表明:1)随埋深h的增加,沉降槽宽度W介于开挖隧道之间,集中在某一区域,当h≥20.0 m时,变化不大;2)W随隧道空间角度θ变化发生偏移,当θ=0°时,最大沉降值分布均匀,随θ的增加,最大值偏向埋深较大的隧道,θ=45°时的沉降量最大,θ=90°时最小;3)W随隧道间距l的增加而增大,沉降值先增大后减小,当l=25 m时最大,以l=25 m为中心向两端相应减小。其研究结果为此类隧道开挖设计提供参考。

Based on numerical analysis,it＇s established many numerical models of overlapping depth,space angle and horizontal spacing to study the surface subsidence,it shows： 1） with the increasing in h,W is between the excavation tunnel,concentrated in a certain area,little change as h≥20. 0 m; 2） W is shifted with θ,the sediment distribution evenly when θ = 0°,the sedimentation value gradually biases the large buried depth tunnel as increase of θ,when θ = 45° is maximum and θ = 90° is minimal; 3） W increases with the increase of l,the sedimentation value increases firstly and then decreases,when l = 25 m is maximum,is reduced by l = 25 m on both sides. The conclusion provides a reference for tunnel excavation design.