Evaluation of Engineering Properties of Recycled Aggregates and Preliminary Performance of Recycled Aggregate Base Layers

Although there have been several studies about using recycled aggregates to construct recycled aggregate base (RAB) layers, there is a lack of information about the effects of gradation of recycled concrete aggregate (RCA) materials on the performance of such layers. There is also limited information available regarding the use of RCA and recycled asphalt pavement (RAP) materials together in RAB layers. In this study, three test cells were constructed with RAB layers using two different RCA materials with different gradations and a blend of RCA and RAP materials, and another cell was constructed with a natural aggregate base layer. Physical characteristics of the base layer aggregates were determined, and resilient modulus (MR) tests were performed. A series of falling weight deflectometer (FWD) tests were performed in the field, and changes in air and soil temperatures over time were monitored. This paper contains detailed information about the evaluation of the engineering properties of recycled aggregates and the preliminary performance of the constructed RAB layers. (C) 2022 American Society of Civil Engineers.

Automated summary

Although there have been numerous studies on constructing recycled aggregate base (RAB) layers using recycled aggregates, there is limited information on the impact of the gradation of recycled concrete aggregate (RCA) materials and the combined use of RCA and recycled asphalt pavement (RAP) materials in such layers. This study aimed to address these knowledge gaps by constructing test cells with RAB layers using different gradations of RCA materials and a blend of RCA and RAP materials. The evaluation of the engineering properties of recycled aggregates and the preliminary performance of the constructed RAB layers were conducted through physical characteristic determination, resilient modulus (MR) tests, falling weight deflectometer (FWD) tests, and temperature monitoring.