Performance evaluation of a polyurethane-urea binder for asphalt pavement groove-filling

Grooved grouting surface pavement has certain advantages in ice-suppression and ice-breaking, and would not cause damage to the surrounding environment. However, when ordinary polyurethane (PU) is used as the binder of grouting material, the interfacial adhesion and durability between grouting material and asphalt mixture are insufficient. Therefore, a new polyurethane-urea (PUU) binder was prepared for the surface pavement of groove grouting in this study. Firstly, the gelation time of PUU binder with different polyuria (PUa) content was tested. Then, the mechanical properties of PUU binder were verified through the shore A hardness test, tensile strength and dynamic thermal mechanical analysis (DMA). The interfacial bonding properties of PUU binder were tested by shear and pull-out tests The UV aging mechanism of PUU binder was revealed by means of Fourier transform infrared spectroscopy (FTIR), Scanning Electron Microscope (SEM) and Tensile strength test. Finally, the wear resistance of PUU binder was verified by Akron wear test. The test results show that the allowable content of ethyl acetate should be controlled within 5–10%. The mechanical properties of PUU were significantly improved by adding a certain proportion of PUa. When the content of PUa is 30% and 40%, the interfacial bonding strength of PUU binder increases significantly, in which the Shear strength increases by 17.1% and 18.1%, and the Pull-out strength increases by 31.7% and 34.9%, respectively. In conclusion, the recommended dosage range of PUa is 30–40%.