Long-Term Performance Evaluation of Concrete Pavements Containing Recycled Concrete Aggregate in Oklahoma

Abstract

To overcome the challenges associated with natural aggregate shortage and the disposal of construction and demolition waste, recycled concrete aggregate (RCA) has been increasingly used in Portland cement concrete (PCC) pavement as a virgin aggregate replacement. The work in this study involved conducting a performance evaluation of the existing RCA-PCC pavements in Oklahoma from different aspects, including: laboratory determination of mechanical properties; a petrographic examination of the concrete; a field evaluation using a falling weight deflectometer (FWD) testing; and distress surveys to assess pavement behavior. The laboratory testing of the field cores confirmed that the addition of RCA into PCC causes a reduction in the modulus of elasticity and tensile strength; the reclaimed mortar was found to be the primary weak zone through which cracks pass. The surface condition survey data and analysis of the FWD results match each other, indicating that the RCA joined plain concrete pavement (JPCP) section exhibited lower performance compared with the control JPCP section. But this trend was not as definitive for continuously reinforced concrete pavement (CRCP). The relatively good performance of the RCA CRCP results from the section being rested on a stronger asphalt concrete base layer. Additionally, the inherent stiffness fundamental to the behavior of CRCP provides a superior level of protection of the base from erosion damage compared with a jointed pavement. The findings indicate that erosion-resistant base support and good load transfer are essential design considerations for JPCP made of RCA-PCC. CRCP appears to be more suitable for the use of RCA-PCC.