Evaluation of cement stabilized recycled concrete aggregates treated with waste oil and asphalt emulsion

Abstract

This research was undertaken to comprehensively evaluate the performance of cement stabilized recycled concrete aggregates treated with waste oil and asphalt emulsion from the aspect of strength, stiffness, and shrinkage properties. A suite of laboratory tests were carried out, including vibratory compaction test, unconfined compressive strength (UCS) test, indirect tensile strength (ITS) test, resilient modulus test, drying shrinkage test, and temperature shrinkage test. The results of UCS and ITS tests showed that both treatments resulted in an acceptable reduction in early-age strength of mixture, but later the treated mixtures had a relatively rapid increase in strength compensating for this deficiency to some extent. The asphalt emulsion treated mixture has a higher strength than the mixture treated with waste oil. The results of resilient modulus test showed that both treatments effectively decreased the stiffness of mixture within the appropriate range and this decrease was much pronounced for the mixture treated with waste oil. The drying shrinkage test indicated that drying shrinkage properties of mixture were improved obviously after treatments and waste oil treatment produced a better effect compared with asphalt emulsion treatment. Furthermore, both treatments also caused a slight improvement to temperature shrinkage properties of mixture revealed by temperature shrinkage test. Overall, both treatments have achieved a satisfactory effect and the use of waste oil and asphalt emulsion is environmentally friendly.