【摘要】 研究隧道施工地表沉降量需有精确估算。为了减少盾构机隧道挖掘所引起的地表沉降,利用FEPG系统,结合盾构法施工的实际过程,综合考虑了开挖面泥水压力、应力释放、注浆力学性质变化、盾构机身坡度、注浆压力等要素,建立了三维非线性有限元模型,对上海崇明越江隧道特大泥水盾构施工进行了数值仿真。仿真计算所得的地表沉降量结果与施工现场测得的实际地表沉降量较为吻合,表明仿真方法的有效性,并对数值仿真影响地表沉降的主要因素进行了分析。从结果分析上看,施工中合理地增大开挖面泥水压力、注浆压力可以有效减小地表沉降。更多还原

【Abstract】 To decrease the ground settlement caused by shield tunneling,a 3D nonlinear finite element model is presented to simulate Chongming river-crossing shield tunneling in Shanghai.The simulation is based on Finite Element Program Generator(FEPG) system and takes into account all relevant components of construction process,such as the slurry pressure at the excavation face,the release of stress,the time dependence of the grout material characteristics,taper of shield skin and grout pressure,according to the practical process of the tunneling.The ground settlement by numerical simulation is validated by the comparison with field measurements,which shows the rationality of this simulation method.On this basis,the influence of main factors causing ground settlement is studied through numerical simulation.From impact analysis,the settlement can be effectively decreased by the reasonable increase of the slurry pressure at the excavation face and the grout pressure.更多还原