The Influence of Frost Heave on Voids of CRTS I Slab Track

Subgrade frost heave may lead to the voids between track slab, concrete roadbed, and subgrade surface, which will increase the stress of track structure. In the case of badly sealed track structure, with moisture flowing into the voids, frost heave will further develop and simultaneously aggravates the destruction of track structure, and affects the operation safety. With the aim to analyze the voids between track slab, concrete roadbed, and subgrade surface under the condition of different concrete roadbed lengths, different frost heave wavelengths, amplitudes, and positions, the paper builds the subgrade frost heave transfer model for CRTS I slab track using the finite element software ABAQUS. The results show that slab track with 10 m long concrete roadbed performs worse than 20 m long concrete roadbed judging from the slab track voids caused by frost heave. The most unfavorable position of frost heave varies with the wavelength. When the frost heave wavelength is shorter than 5 m, the most unfavorable position is to set the frost heave slope toe at the concrete roadbed joint; when the range of wavelength is between 5 m and 20 m, the most unfavorable position is to set the frost heave peak far from the joint about a quarter length of the concrete roadbed, and when the wavelength exceeds 20 m, the position will have little effect on void of track structure. The void height of track structure will increase first and then decrease, finally tend to be zero with the increase of the wavelength when the frost heave rate remains unchanged. The maximum void height appears when the frost heave wavelength is about 10 m.