Improving the Performance of Lightweight Crumb Rubber Mortar Using Synthetic, Natural, and Hybrid Fiber Reinforcements

The global market for tires is ever-growing, and partially replacing sand with crumb rubber (CR) as fine aggregates in concrete could reduce environmental pollution. However, the main barrier to complete usage of recycled tire crumbs construction deterioration effect CR on mechanical properties cement-based composites. Therefore, this paper attempts improve fresh hardened mortar (CRM) by incorporating polypropylene-polyethylene synthetic fibers coconut kenaf natural reinforcements. A total 18 mix designs were developed varying fiber combinations replacement. Subsequently, parametric studies chemical admixture conducted at 3, 7, 28 days flowability resulting fiber-reinforced CRM. According results, single hybrid positively improved cement 5–15% It can be concluded that adding enhanced performance modified providing degrees improvement.