Evaluation of hot mix asphalt made with recycled aggregates from demolition waste (RADW) coated with bitumen emulsion

Abstract

Several researches and studies were done in the field of using the recycled aggregates (RA) in hot mix asphalt (HMA), especially the recycled concrete aggregates (RCA). In this study, we investigated the possibility of using the recycled aggregates from all types of the demolition waste not only the recycled aggregates from concrete RCA. In the previous researches, the RCA were placed as a percentage of the natural aggregates used in HMA, but in this study we examined the possibility of using recycled aggregates from demolition waste (RADW) instead of natural aggregates which means using RADW with 100% of asphalt aggregates. Therefore, we could achieve the full utilization of the demolition waste that represents a big environmental problem especially in Egypt. In this study, three samples of demolition waste aggregates with different components were used in preparing HMA mixtures to produce three types of HMA mixtures (mix 1–mix 2–mix 3) and a mixture with natural aggregates was prepared to produce the control mix. After determining the optimum asphalt content of each mixture, the four mixtures conducted to several performance tests to find the optimum components of demolition waste in HMA mixture and the possibility of using a HMA mixture with 100% RADW. By reviewing the previous studies at that field, we got very important information about coating the RA by bitumen emulsion to present a performance similar to the natural aggregates in HMA.