If a project crosses below an existing high-speed railway bridge, it is likely that when the project is constructed or operated after being put into use, the dead and live loads of the project below the bridge will cause vertical and lateral movements of the surrounding soil of the high-speed railway. And then the additional stress will be produced, which may cause vertical settlement and lateral displacement of the foundation of the existing high-speed railway, posing a threat to the operation safety of the existing high-speed railway if the settlement or displacement is too large. This paper, in combination with a under-construction container-transportation five-track railway project crossing below the existing Tianjin-Qinhuangdao high-speed railway bridge, employed the Plaxis finite element program of pile-soil interaction and other softwares, and analyzed the influence of the soil movement on the safety of the Tianjin-Qinhuangdao high-speed railway bridge from the aspects of bearing capacity, deformation, settlement and so on. The analysis result indicated that the influence on settlement would exceed the allowed value and there would be safety risk if crossing below the Tianjin-Qinhuangdao high-speed railway bridge in the form of subgrade structure. Therefore, the below-crossing scheme was changed from subgrade structure to pile-sheet structure.%下穿既有高速铁路桥梁工程，施工期间及运营阶段的桥下工程恒载及活载影响，会导致既有高速铁路周围土体发生垂直和水平运动，产生的附加应力会引起临近的既有高速铁路基础产生竖向沉降及侧向位移，数值过大甚至会影响到高速铁路运营安全。结合某在建集装箱五线铁路下穿已建成的津秦高速铁路桥梁工程，利用桩土共同作用有限元程序plaxis等有限元软件，从承载力、水平变形及沉降等方面分析土体运动对津秦高速铁路桥梁的安全影响。分析结果表明，以路基下穿津秦高速铁路方案沉降影响超出允许范围，存在安全风险，后改为桩板结构下穿。
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