Stability Analysis of Tunnel in Yangtze Estuary Under Dynamic Load of High-Speed Railway

The section from Shanghai to Hefei along the Yangtze River is located in the territory of Shanghai, Jiangsu and Anhui provinces in East China. There is one tunnel in the whole line, which is the Yangtze River tunnel along the Yangtze River. The total length of the tunnel is 14,150 m, in which the total length of the section under the Yangtze River is 10,360 m, with the maximum soil covering of about 39 m and the maximum underwater burial depth of about 67 m. The project is located at the mouth of the Yangtze River, and there are some unfavorable geology, such as saturated soft soil (silty) and fine sand formation. From the perspective of train-track-structure-stratum coupling effects, the interaction mechanism between tunnel and stratum under long-term cyclic load is explored. Combined with the actual geological parameters and engineering parameters, the dynamic response of the train structure under cyclic load is numerically simulated. Through the results of numerical simulation, the tunnel life under the train load is evaluated from the perspective of cyclic load fatigue failure, and the necessity of the tunnel lining structure is analyzed from the perspective of structural dynamic response.