Effects of debonding repairment on interfacial damage and thermal deformation of CRTS II slab ballastless track

The effects of debonding repairment on the interfacial damage and thermal deformation of CRTS II slab bal-lastless track are further assessed in this work. An improved mixed-mode bilinear cohesive zone model was adopted in an attempt to obtain a more accurate prediction of the interfacial damage. A finite element model of CRTS II slab ballastless track was built with the debonding repairment considered, based on which the interfacial damage and structural deformation of CRTS II slab ballastless track were simulated under the field-measured temperature gradient loads. The results show that the debonding repairment restores the capacity of CRTS II slab ballastless track to resist the thermal deformation, but that capacity will gradually decrease with the accumulation of interfacial damage. The re-debonding in the upper interlayer of CRTS II slab ballastless track, which may happen after a one-year cyclic temperature gradient load, will result in the emergence of an opposite -sided debonding in the lower interlayer. In addition, implementing the debonding repairment with the rebars-implanting has significant impact on reducing the re-debonding height.

Automated summary

The effects of debonding repairment on interfacial damage and thermal deformation of CRTS II slab ballastless track are evaluated in this study. An improved mixed-mode bilinear cohesive zone model is utilized to provide more accurate prediction of the interfacial damage. A finite element model of CRTS II slab ballastless track, considering debonding repairment, is developed to simulate the interfacial damage and structural deformation under field-measured temperature gradient loads. The results indicate that debonding repairment restores the thermal deformation resistance of CRTS II slab ballastless track, but this capacity gradually decreases with the accumulation of interfacial damage. Re-debonding in the upper interlayer may lead to the emergence of an opposite-sided debonding in the lower interlayer. Furthermore, implementing debonding repairment with rebar implantation significantly reduces the re-debonding height.