EXPERIMENTAL INVESTIGATION ON HOT MIX ASPHALT BY PARTIAL REPLACEMENT OF CRUMB RUBBER AS FINE AGGREGATE AND WASTE GLASS POWDER AS FILLER

Abstract

Asphalt pavement refers to any paved road surfaced with asphalt. Hot Mix Asphalt (HMA) is a combination of approximately 95% stone, sand, or gravel bound together by asphalt cement, a product of crude oil. Asphalt concrete is heated aggregate, combined, and mixed with the aggregate at an HMA facility. As the rapidly growing number of vehicles in Ethiopia, the waste of tyre rubber becomes a major environmental concern. The Glass wastes also kill wildlife, contribute to environmental stressors through continuous recreation, and play a significant role in both air and water pollution. In many nations, properly disposing of the enormous volume of waste glass has emerged as a severe environmental challenge. This study aims to investigate the effects of crumb rubber as fine aggregate and waste glass powder as filler on hot mix asphalt. In this study grade 60/70 bitumen used and investigate the effect of replacing crumb rubber as fine aggregate and Waste Glass Powder as mineral filler to asphalt mixture. The laboratory hot mix asphalt design tests were done by Marshall Method procedure. In this study, four different crumb rubber contents (11%, 22%, 33% and 44% by weight of fine aggregate) and waste glass powder contents (25%, 50%, 75% and 100% by weight of mineral filler). The result of marshal stability at 75% show a maximum strength of waste glass powder replacement in filler, 22% crumb rubber in fine aggregate and combined mix 75% glass powder and 22% crumb rubber at 4.67% optimum bitumen content in the production of asphalt mixture. Also, indirect tensile strength value for WGP75% with CR33% is 0.71 and 0.8 for conditioned and unconditioned respectively. The moisture susceptibility value was 89.3% at WGP75% with CR33%. Marshal stability up to 75% replacement of waste glass powder in mineral filler is greater than that of the minimum requirements. Beyond 33% crumb rubber replacement the stability, flow, indirect tensile strength and moisture susceptibility show reduction. From this study finding, it can be concluded that a combination of both types of waste glass powder at 75% and crumb rubber at 33% replacement can be recommended for use in asphalt road construction.