Evaluating the Fatigue Resistance of Sustainable Modified Binder Blends
摘要
Fatigue failure is one of the most common failures in the road pavement sectors that costs nations billions of dollars annually. Fatigue resistance is the ability of an asphalt mixture to resist repeated traffic loads under the surrounding environmental conditions without being fractured. Fatigue performance assessment, based on the laboratory testing, is considered not reliable since the performance grades (PG) obtained from the Dynamic Shear Rheometer (DSR), along with the G*sin(δ) fatigue parameter, for the tested asphalt is only based on small strain rheology and do not consider the damage resistance. Accordingly, the Linear Amplitude Sweep (LAS) test is implemented to study the fatigue behavior of the tested asphalt binders, considering the damage. The primary goal of this research is to investigate, via various experimental testing, how various modified asphalt binders that employ various sustainable waste materials behave in terms of fatigue cracking resistance. Using the conventional DSR parameter (G* sin δ), the study investigates the fatigue cracking resistance of various modified asphalt binders, including crumb rubber (CR), low-density polyethylene (LDPE), blend of CR and LDPE, and fiber-elastomer commercial modifier (Viatop). Based on that, in order to determine the fatigue cracking potentials, the study compares the LAS characterization of the various waste-modified asphalt binders with the classical DSR characterization. In light of that, the study recommends the eco-friendly waste modifier that has the best chance of improving fatigue cracking resistance. Based on the results, the most promising mixes to withstand fatigue cracking are CR + LDPE, followed by CR modified asphalt blends.