Research conclusions:(1)In winter, the track slabs are mostly in tension，and cracking damages lie in dummy joints; in summer, the track slabs are basically compressed，only the area under the slab bottom near the dummy joints is in tension locally.(2)The maximum stress in the track slab，CA mortar and the supporting layer decreases with the increase of time，while the vertical deformation increases with time increasing, and both stress and vertical defomation will be gradually stabilized in about twenty years.(3)In addition to the dummy joints ( joint seams)，the track slabs have no serious fatigue damage area, and the cracking damages development of dummy joints ( joint seams) would be stabilized in five years，eventually the cracking area ratio of each section will be approximately stable at about 0. 7. (4)This paper can provide the theory basis for the design，maintenance and repair of the CRTS II slab ballastless track structure on subgrade.