Study on horizontal and vertical temperature gradient of ballastless track on bridge in cold season

By means of holding a continuous observation of CRTS II by using temperature sensors on curve line, the time-dependent rules of temperature changing and distribution in the track structure with superelevation could be found out. The analysis results prove that: the changing of the temperature in the track structure is on a 24 h cycle. The temperature changing value becomes small and the time of maximum temperature comes late with the increase of distance to surface. Fitting curve of vertical temperature gradient in longitudinally connected ballastless track on curve line can be exponential curve, and the curve sharp is similar to the provisions about the vertical temperature gradient of the code for design of bridge and culvert in China. The horizontal temperature gradient includes the track slab and support layer, temperature gradient of track slab can be fitted by using quadratic function, and temperature gradient of support layer can be fitted by using piecewise linear function. ©, 2015, Huazhong Keji Daxue Xuebao (Ziran Kexue Ban)/Journal of Huazhong University of Science and Technology (Natural Science Edition). All right reserved.