The elaborate nonlinearly coupled dynamic analysis model for track-tunnel-surrounding soils of double line subway was established.The infinite of foundation was modeled using three dimensional static-dynamic unified viscoelastic artificial boundaries.Based on the material nonlinearity,contact nonlinearity and the static stress state prior to the commercial operation of the subway tunnel,the dynamic behaviors of subway tunnel and surrounding soils under moving loads were investigated.It is found that the elements located at different positions in the circumferential direction of the tunnel lining experienced loading and unloading repeatedly during the movement of loads.All the elements were in low dynamic stress level but with remarkable rate effects.The response of dynamic stresses demonstrated relatively strong regular form for the elements located near the loaded rails and showed inconspicuous regular form for the elements far from the loaded rails.The soil element located just below one of the loaded rails near the tunnel lining was mainly in compression state with low dynamic stress level but high rate effects.The stress states of tunnel lining for fixed cross section at different times or for different cross sections at specified time entirely differed from each other.The variations of resultant axial force and resultant bending moment of tunnel lining were inconsistent with each other.%构建精细化双线地铁轨道-隧道结构-围岩非线性耦合系统动力分析模型,以三维黏弹性静-动力统一人工边界模拟地基无限域,考虑材料非线性、接触非线性和隧道运营前的静应力状态,研究移动荷载作用下地铁隧道和围岩的动力行为.结果表明:荷载移动过程中,隧道衬砌周向不同位置均经历了多次加、卸载过程;衬砌的动应力水平较低但速率效应明显;受载钢轨附近位置的动应力响应规律性较强,较远位置的动应力响应无明显规律;受载钢轨正下方靠近衬砌处的土单元以受压为主,其动应力水平较低但速率效应较大;同一断面衬砌在不同时刻和同一时刻不同位置处断面受力状态不同,其轴力合力与合弯矩的变化不完全一致.
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