| With the development of high-speed railway and the construction of large-scale passenger line in China, the design theory of ballastless track has also been a rapid development and application. However, damaged cracks of the main concrete structure of the ballastless track was unavoidable taking into account a variety of factors such as the vehicular load or temperature influences. The crack of the track bed may have some influence on the stress of the track and the vibration of the wheel-rail system, thus affecting the long-term life of ballastless track. Therefore, it is necessary to establish the analysis model of the ballastless track with cracks, and to study the mechanical behavior of the ballastless track, thus can provide the necessary theoretical basis for Optimum Design and Maintenance of the ballastless track.To study the stress of the CRTS I bi-block slab track with cracks, I have established a space finite element model of the CRTS I bi-block slab track with initial cracks first in this paper, based on the finite element method according to its structure. In this model, the interaction between steel and concrete and concrete plastic (ie, material nonlinear) has been taken into account. Then analyzed the track bed deformation, the crack opening displacement and the bar stress of the ballastless track with cracks, and the effect on the crack opening displacement and the bar stress by the crack depth and the reinforcement ratio. Then analyzed the stress of the ballastless track with cracks under the temperature stress, obtained the crack opening displacement and the bar stress. And analyzed the effect on the crack opening displacement and the bar stress by the crack depth, the reinforcement ratio and the temperature value. Finally, analyzed the stress of the CRTS I bi-block slab track with cracks under the vehicular load and the temperature stress joint action, obtained the crack opening displacement and the bar stress, and analyzed the effect on the crack opening displacement and the bar stress by the crack depth and the reinforcement ratio.We can get the conclusion from the above analysis:(1) The crack opening displacement has increased gradually with the increase of crack depth under the vehicular load. Within a certain range, the reinforcement ratio of the track bed has no effect on the crack opening displacement of the ballastless track. (2) The effect on the crack opening displacement and the bar stress by the crack depth and the reinforcement ratio is not significant under the temperature stress. From the point of view of the amount, the crack opening displacement is an order of magnitude higher than under the vehicular load. The crack opening displacement and the bar stress has increased linearly with the increase of the temperature drop under the same depth of crack. |
