Performance Characterization of Hot In-Place Recycled Asphalt Mixtures

Abstract

Despite the widespread use of in-place recycling, limited information is available in the literature on in situ and laboratory properties of materials placed through in-place recycling. The main objectives of present study were to investigate the in situ recycled material characteristic that includes the potential of asphalt mixtures for permanent deformation, fatigue cracking, and low-temperature cracking, and the effect of a special technique of hot in-place recycling and rejuvenation on asphalt binder rheological properties. To accomplish these objectives, a two-phase experimental program was designed to determine the performance-related parameters of 100% in-place recycled mixtures using one of the in-place recycling techniques in which overlay is not needed. The experimental program included the measurement of mixtures’ mechanical properties and binder rheological properties. The present study revealed that the stiffness of the asphalt mixtures after recycling had increased compared to that before recycling. In general, specimens exhibited a low permanent deformation potential of 2–3 mm after 20,000 loading cycles by using the Hamburg wheel-track test. Stable crack propagation could not be obtained in the fracture tests at