某节理岩体隧道开挖引起地表沉降离散元数值分析

Discrete element numerical analysis of surface settlement caused by excavation of a jointed rock mass tunnel

隧道开挖引起地表沉降的问题一直是隧道施工单位密切关注的问题之一。针对某隧道所处的节理岩体条件,通过现场监测和UDEC离散元数值模拟,对节理岩体隧道开挖引起地表沉降特征进行了分析。结果表明:节理岩体浅埋隧道开挖引起地表沉降曲线呈现偏态性,而非正态分布曲线;节理岩体隧道开挖变形首先由岩体节理弱面产生滑移,并不断向上方地表传递。

The problem of surface settlement caused by tunnel excavation has always been one of the issues closely concerned by tunnel construction units.In this paper,the characteristics of surface settlement caused by excavation of jointed rock mass are analyzed by on-site monitoring and UDEC discrete element numerical simulation for the jointed rock mass conditions of a tunnel.The results show that the surface settlement curve caused by excavation of shallow rock tunnel in jointed rock mass is skewed rather than normal distribution curve.The excavation deformation of the jointed rock mass tunnel is firstly caused by the slip surface of the rock mass joint and is continuously transmitted to the upper surface.