Study on the effects of solar reflective coatings on the interfacial damage of the CRTS II slab track

In this work, the effects of novel solar reflective coatings on interfacial damage of the China Railway Track System (CRTS) II slab track were studied. Firstly, the effects of two different types of solar reflective coatings on the non-linear temperature distribution of the track slabs were investigated. Then, the influence of the solar reflective coatings on the damage of the interface between the concrete slabs and the cement asphalt mortar layer was studied based on a finite element model of the CRTS II slab track incorporating a bi-linear cohesive zone model of the interface. Finally, the effects of interface bonding properties on the interfacial damage of the coated tracks were analyzed by the finite element model. Results show: The interfacial damage can be underrated if linear rather than non-linear temperature distribution of the track slabs is applied. Both types of coatings can mitigate interfacial damage and reduce slab vertical displacement significantly compared with the uncoated tracks, while the organic solar reflective coating shows better performance than the inorganic solar reflective coating. To avoid interface debonding, the interface bond strength of the coated tracks should be larger than 0.02 MPa.