基于有效应力分析法,运用有限差分程序FLAC3D建立了盾构隧道主隧道、联络通道、地层相互作用三维计算模型。分析了两辆列车单次交汇运营条件下。联络通道与隧道结构连接处典型断面特征点处土层孔隙水压力、盾构隧道衬砌结构变形及主应力变化。计算结果表明:在列车振动荷载作用下离隧道拱底越近的土层,孔隙水压力与初始有效应力的比值越大。但均小于1,土体尚未达到发生液化的条件;衬砌结构位移最大值出现在盾构隧道拱底,为0.16mm;衬砌结构拉、压应力最大值均未超过结构抗拉、抗压强度设计值。表明衬砌结构在列车振动荷载作用下是安全的。
Based on effective stress analysis method, the main tunnel, connected aisle and formation interaction three-dimensional calculation model was proposed by finite difference program FLAC3D. On condition of single-time intersection of two trains, pore water pressure, deformation and principle stress of the typical section characteristic points of junction between the connected aisle and tunnel was emphatically analyzed. The results show that: under train vibration load, the closer the soil layer from the arch bottom, the larger the PPR, but all are smaller than 1, which still cannot reach the condition of liquefaction; the maximum displacement of lining appears at the arch bottom, of which the value is 0.16 mm; the maximum tension-compression stress of lining are all smaller than its design value of corresponding strength, which shows that the lining is safe under train vibration load.