Abstract:The low temperature performances of rubber modified asphalt and crumb rubber composite SBS modified asphalt with the different contents are analyzed through the bending beam rheometer (BBR) test. The results show that with the increase of crumb rubber content, the stiffness modulus of rubber modified asphalt gradually decreases, the creep rate gradually increases, the asphalt gradually softens, the low temperature deformation and the stress dissipation capacity gradually improve, and the low temperature performance gradually improves. As the content reaches 18%, its low-temperature performance grade (PG) can be upgraded by one level compared with the base asphalt. For crumb rubber composite SBS modified asphalt, with the addition of SBS, the stiffness modulus of the rubber modified asphalt slightly increases while the creep rate also increases. It is explained that the addition of SBS makes the rubber modified asphalt rubber hardened, and also its low temperature deformation and stress dissipation capacity are improved. As the rubber powder content increases from 5% to 18%, its low temperature stiffness modulus decreases by about 50%.
