【摘要】 文章以沈阳富水地层盾构管廊工程为研究背景,对土压平衡盾构开挖引起的地表竖向位移和水平位移进行监测,并分析位移的变化规律。以现场测量得到的位移监测值为基础,基于粒子群优化的BP神经网络算法建立PSO-BP参数反演分析方法,利用Fortran语言编制位移反分析程序,并采用正交设计和ABAQUS数值计算进行参数反演。考虑静止土压力、主动土压力和被动土压力对掌子面稳定性的影响,根据反演的参数对盾构廊道掌子面的支护压力进行分析。研究结果表明:所建立的PSO-BP参数反演分析方法是一种可行、有效的反分析方法。当支护压力比λ=0.4时,掌子面处于极限状态;随着支护压力比的减小,地表沉降呈增大趋势。当考虑地下水作用时,为了保证掌子面的稳定需要增加支护压力;当支护压力比λ=0.6时,掌子面处于极限状态。更多还原

【Abstract】 Taking the Shenyang utility tunnel project in water-rich strata as the research background, which is excavated by a EPB shield machine, the vertical displacement and horizontal displacement of the ground surface caused by the EPB shield tunnelling are monitored, and the displacement development law is analyzed. According to the actual measured displacement data, the PSO-BP parameter inversion analysis method is established based on the particle swarm optimization algorithm. The displacement inverse analysis program is compiled using Fortran language, and the parameter inversion is performed using orthogonal design and ABAQUS numerical calculation method. Considering the effects of static earth pressure, active earth pressure and passive earth pressure on the working face stability, the limit supporting pressure on the shield-driven utility tunnel face is analyzed according to the inversedsoilparameters.TheresultsshowthatthePSO-BPparameterinversionanalysismethodisafeasibleandeffective method. When the supporting pressure ratio is 0.4, the working face is in the limit state; and with the decrease of the supporting pressure ratio, the ground surface settlement maintains an increase trend. When the effect of groundwater is considered, larger supporting pressure should be needed to ensure the stability of the working face;and the working face is in the limit stat when the supporting pressure ratio is 0.6.更多还原