Rheological Response of Asphalts

The rheological response of asphalt cements to shearing stresses is presented. The behavioral characteristics were measured using a rotating coaxial cylinder viscometer. Little or no development of theory is presented. The viscoelastic portion of deformation is discussed in terms of the creep function. Plastic deformation is described using the definitions of apparent and plastic viscosities. Curves showing the effects of temperature, stress level and penetration on these two major components of strain are presented and discussed. Analysis indicated that plastic deformation is the predominant component of strain and, thus, should be considered and incorporated in the design of flexible pavements