Mixture and production parameters affecting cracking performance of mixtures with RAP and RAS

Abstract

Many methods and approaches have been developed to evaluate the asphalt performance in the laboratory. The laboratory testing can be conducted on mix design (lab produced) and QA/QC (plant produced) stages. To predict the asphalt field performance, an understanding of differences between the behavior of lab and plant produced mixtures is required. There are many factors in the design and production of recycled mixtures that can potentially impact the performance of the in-place material. The project involves testing of both laboratory and plant produced mixtures containing 20-30 % recycled materials (RAP and RAS) by total weight. The mixtures have different gradations (12.5 and 19 mm NMSA), and contain different virgin binder PG grade (PG 58-28, and PG 52-34). The characteristic damage curves and failure criterion diagrams of mixtures are developed based on fatigue testing following the simplified viscoelastic continuum damage (SVECD) protocols. The results show that the most of lab produced mixtures have better fatigue properties in damage characteristics, but they do not follow a consistent trend in fatigue life.