Effect of wetting and drying cycles on mechanical strength of cement-natural rubber latex stabilized recycled concrete aggregate

• DOI: 10.1016/j.conbuildmat.2023.132301
• Publication Date: 2023-06-28T18:20:14Z
• Authors: Menglim Hoy; Duong Vinh Nhieu; Suksun Horpibulsuk; Apichat Suddeepong; Avirut Chinkulkij...; Apinun Buritatum; Arul Arulrajah
• Keywords: Subbase; Crumb rubber; Ductility (Earth science)

In this study, natural rubber latex (NRL) was used as a polymer additive to modify the durability against wetting and drying (w-d) cycles of the cement-stabilized recycled concrete aggregate (RCA) when used as a pavement base/subbase material. This research investigated the performance of cement-stabilized RCA and cement-NRL stabilized RCA at various dry rubber-to-cement (r/c) ratios against w-d cycles. The weight loss, unconfined compressive strength (UCS), rate of deterioration, modulus of elasticity, and microstructural analysis of the studied samples before and after being subjected to w-d cycles were performed. The r/c ratio of 10% was found to be the optimum r/c ratio for cement-NRL stabilized RCA, which provided the best performance for all test results. The weight loss was found to increase, while the UCS value subsequently decreased with an increase of w-d cycles for all studied samples. At the optimum r/c ratio, the UCS results of cement-NRL stabilized after 12 w-d cycles were still higher than the minimum requirement (UCS > 2.413 MPa) for a high-volume traffic road. In addition, its modulus of elasticity was higher than that of cement-stabilized RCA samples. This indicated that the NRL additive could enhance the ductility of cement-stabilized RCA. The microstructural analysis illustrated that the formation of a stable cross-linked matrix between the cement hydration products and NRL films could improve the durability against the w-d cycles of cement-stabilized RCA as a pavement base material.