Effect of Temperature Gradient Load on Interlayer Damage of CRTS Ⅱ Slab Track

Research purposes: To investigate the influence of temperature gradient loads on the connection between mortar layer and track slab, a finite element model including a cohesion model between layers of CRTS Ⅱ slab ballastless track was established. The influence of positive and negative temperature gradient loads on the initiation and development of mortar layer gap and the effect of them on track deformations were analyzed. The difference between the two kinds of temperature gradient loads on interlayer damage was compared. Research conclusions:(1) The damage area and deformations of CRTS Ⅱ slab ballastless track increase with the increase of temperature gradient loads. The interlaminar damage caused by negative temperature gradient loads are more serious than that caused by positive ones. (2) When the temperature gradient load is in the range of -10 ~20 ℃/m, it has little effect on the interlaminar damage. (3) Under the same temperature gradient loads, the deformation of track slab is greater than that of mortar layer. Under the positive temperature gradient load, the track structure deformation along the slab edge is greater than that along the slab middle. However, under the negative temperature gradient load, the difference is not significant. (4) The research results can provide theoretical reference for the long-term service performance analysis and maintenance of CRTS Ⅱ slab track of high-speed railways. © 2022, Editorial Department of Journal of Railway Engineering Society. All right reserved.