Analysis of the Influence of Train Dynamic Load on the Side-Crossing Bridge Pile Subway Tunnel

Abstract

In order to explore the influence law of train dynamic load on the side-crossing bridge pile foundation subway tunnel, taking Xi’an Metro Line 14 underneath the Datong-Xi’an High-speed Railway Bridge Project as the background, three-dimensional finite element numerical simulations have been carried out on four working conditions: the subway tunnel shield is not constructed, the shield is constructed to the high-speed rail bridge, the subway right line tunnel is completed, and the subway tunnel is double-line completed. The analysis results show that the train dynamic load is transferred to the tunnel structure of 11.0m underground through the bridge, pile foundation and surrounding strata, the maximum position of the tunnel structure dynamic response is at the haunch, the response of the double-line tunnel is greater than that of the single-line tunnel; the train dynamic load has the greatest impact on the pile top of the bridge pile foundation and the least impact on the pile bottom; the subway tunnel adjacent to the bridge pile reduces the train dynamic response of the pile foundation, when there is no tunnel on the side of the pile foundation, the dynamic response of the bridge pile foundation is the largest, the single-line tunnel comes second, and it is the smallest when there is the double-line tunnel.