LAUSR

In the areas which have rich rain and poor drainage, there may be obvious water damage existed in the interlamination of ballastless track. The damage is mainly caused by repeated hydraulic fracturing. Aimed at this problem, the calculation model of water pressure under the train load was established on the basis of fluid-structure interaction theory, and the influence of crack geometry and train operation condition on water pressure were analyzed. The results show that, when the train is close to and far away from the location of the crack, the water pressure changes periodically under the train load, and the pressure peak occurs at the crack front. Simultaneously, the positive and negative pressure may both exist in the crack. The crack geometry affects the distribution of water pressure significantly, the value of water pressure is inversely proportional to the vertical opening of crack, and proportional to the cubic polynomial of horizontal crack depth. The water pressure increases firstly with the increase of longitudinal crack length, then decreases gradually and tends to be stable finally. The train operation condition is also an important factor affecting the distribution of water pressure, the value of water pressure is linear with the axle load, and proportional to the square of train speed. These research results will provide a hydraulic boundary condition for further study of water damage mechanism.