Fatigue Life Prediction of CRTS I Ballastless Slab Track

In order to predict the fatigue life of ballastless track which is at the section of uneven subgrade settlement, take the CRTS I ballastless slab track for example, considering the rebar of slab and base, a detailed vehicle-ballastless slab track-subgrade coupled model was established based on ANSYS/ADPL. Thus, the time history curve of ballastless track structures under one time train load can be obtained, the typical stress spectrum of which can also be gained through rain flow counting method. Based on the S-N curve of the material and the Miner linear accumulative damage criteria, the fatigue life of ballastless track structures was predicted. Results show that the fatigue damage of slab can be ignored because the stress amplitude of prestressed steel and concrete are both considerably small. The longitudinal tension stress of base concrete is comparatively large, much attention should be paid to control the amplitude of uneven subgrade settlement and the design strength of base concrete. The fatigue life of base can be reached at 3.26x109 under dead load and train dynamic load, ignoring the effects of the other factors.