Research On Temperature And Stress Evolution Of CRTSⅢ Ballastless Track Slab

CRTSⅢ ballastless slab is widely used in Chinese high-speed railway for its easy maintaining and high safety and stability.Exposed to all kinds of environmental effects such as periodic sonar radiation and wind speed,its capacity and sustainability usually becomes poor due to buckling deformation and crack.Thus it is crucial to study the thermal behavior of a CRTSⅢ ballastless slab to keep railway operation safe.This paper study the spatial distribution and time eclipse of sonar thermal field within a ballastless track slabs of high-speed railways.The temperature field is modeled by a combination of in-situ monitor,theoretical analysis and numerical simulation.Specific temperature loading conditions are considered.The study presents as following:(1)A in-situ monitor was undertaken on the CRTSⅢ ballastless track slab to obtain the temperature field character.A temperature field model accounting for environment parameters is built up to best simulate the real condition,which is verified with data.A reference value of temperature gradient is proposed for specific meteorological regions.(2)A numerical model for CRTSⅢ is built up in ABAQUS environment in light of plastic constitutive relation of concrete.The numerical results are compared with available data monitored or already published.(3)The importance of gravity is emphasized according to numerical result.The deformation of slab and subframe are obtained under simulated thermal conditions.Under the most unfavorable case,the thermal isolating coating is considered to minimize thermal response of CRTSⅢ.(4)The GDP forecast model,which arrived at from one-year monitor data,is used to predict the extrema thermal gradient of CRTSⅢ slab in 100 years period.This model is again verified in ABAQUS to obtained a realistic response of the slab.This study provide guideline to a long-term maintaining of CRTSⅢ slab.