Rheological Model and Viscoelasticity of Crumb Rubber Modified Bitumen

Rheological model for crumb rubber modified bitumen (CRMB) by the rheological testing and model analyzer was investigated in this paper. The effects of crumb rubber content and temperature on rheological model and viscoelasticity of CRMB were conducted. The results illustrate that rheological model of bitumen is transformed from Dashpot into Burgers at 60°C after bitumen has been modified by crumb rubber. And the elasticity of CRMB is increased and the viscosity is decreased with crumb rubber content rising. For the modified bitumen with 20% crumb rubber (CRMB-20), its rheological model is Burgers among 20°C~80°C, but the model is translated into Maxwell at 100°C. As the temperature increases, both viscosity and elasticity of CRMB-20 are increased. Compared with 20°C, the instantaneous elastic and viscous deformation of CRMB-20 at 100°C are increased by 14.2 times and 80.5 times, respectively.