Using Frequency Sweep Test to Predict Creep and Recovery Response of Asphalt Binders

Abstract

This paper presents a methodology to obtain creep and recovery response of asphalt binders merely by using frequency sweep tests, which are relatively easier to conduct. This proposed methodology would be useful for practitioners and researchers in modeling time-dependent rutting performance of asphalt binders using simple linear viscoelastic measurements obtained from dynamic shear rheometer (DSR). Frequency sweep tests were conducted on four different asphalt binders at temperatures ranging from 10°C to 70°C. Complex modulus master curves were constructed for 40°C, 50°C, and 60°C followed by presmoothing using a power law and modeling using a Prony series. The estimated complex modulus, which is in frequency domain, was translated into the relaxation modulus, a time domain entity. The relaxation modulus was converted to creep compliance using Laplace transform. The resultant creep compliance was modeled using a generalized Burgers model (GBM), which was used for predicting creep and recovery response of asphalt binders for different loading and unloading periods. The predicted creep and recovery profiles were successfully validated with the multiple stress creep and recovery (MSCR) measurements obtained at 40°C, 50°C, and 60°C for all binders.