Utilizing Simplified Viscoelastic Continuum Damage Model to characterize the fatigue behavior of Styrene-Butadiene-Styrene (SBS) modified binders

Abstract

Rapid traffic growth, extreme climatic condition, and thickness reduction enthusiasm lead to an increase in the use of Styrene-Butadiene-Styrene (SBS) polymer in pavement industry. However, past studies have shown that the Superpave binder parameter for fatigue, |G*|sinδ has failed to characterize the fatigue performance of the polymer modified binders (PMBs) due to its complex structure and interaction with the binder. This study utilizes the Simplified Viscoelastic Continuum Damage (S-VECD) model with the newly developed Linear Amplitude Sweep (LAS) test to investigate the fatigue potential of PMBs with different content of SBS polymer and their correlation with mixture fatigue performance from the Four Point Flexural Beam (FPFB) test. This study also performs the Time Sweep (TS) fatigue test to verify the S-VECD prediction from the LAS test data with respect to measured fatigue life, Nf. Results show that the LAS test along with the S-VECD can successfully explain the fatigue performance of PMBs. It is found that the S-VECD predicted Nf from the LAS test data is consistent with the measured Nf from the TS test. This study also observes that there is a strong relationship between binder Nf from the LAS test and mixture fatigue endurance limit (FEL) from the FPFB test.