Performance of Bituminous Mixes Containing Emulsion-Treated Recycled Concrete Aggregates

Abstract

Use of recycled concrete aggregate (RCA) in bituminous paving mixes is limited because of its high water absorption. Therefore, in this study, an attempt has been made to pretreat RCA using bituminous emulsion to reduce its water absorption characteristics, which is referred to in this study as pretreated recycled concrete aggregates (PRCAs). In the second stage, dense bituminous macadam (DBM) paving mixes were prepared using PRCA, RCA, and natural aggregate (NA) as coarse aggregates, with two different types of filler, i.e., cement (CM) and stone dust (SD), and the performance was studied through various tests such as Marshall test parameters, indirect tensile strength, moisture susceptibility, dynamic modulus, and wheel-tracking test for rutting. It was observed that the PRCA and RCA mixtures, in general, satisfy the requirements in terms of Marshall test parameters and moisture susceptibility. Also, from the dynamic modulus and rutting tests, the mixtures containing PRCA showed good results compared with DBM mixes prepared with virgin aggregates. Cement as filler was found to produce better engineering properties compared with stone dust.