railway tunnels;  dynamic response;  moving loads;  High speed

The processing method of moving load is obtained from the differential equation of forced vibration of the beam, and the dynamic response of the railway tunnel under high-speed moving load is analyzed on the basis of the excavation static field, considering the temporal and spatial effects of the load. The results show that the maximum dynamic response of the structure occurs at a certain moment after the wheelset passes the measurement point, and slightly lags behind the passing point of the time. The vertical displacement, acceleration and dynamic stress of the structure increase with the increase of driving speed, among which the upward arch stress is the most sensitive to driving speed. The high stress area is mainly concentrated in the inverted arch and side wall, which are the weak points of the tunnel dynamic design. Under the load of train, the structural failure is mainly controlled by the tensile strength.