• Aadil Nazir Naikoo
• Waseem Akram Bhat

This paper presents the results of a study on the rubber modified asphalt concrete mix. In this study, partial replacement of aggregates was done with the crumb rubber aggregates in the bituminous concrete layer of 13.2mm nominal size as per IRC.The partial replacement was not carried on the overall grades of the Bituminous Concrete layer but only three sizes of aggregates were being put to partial replacements. The grades like 2.36mm, 1.18mm, and 0.600mm were partially supplanted. The whole study is composed of the laboratory evaluation of the bituminous concrete mix in which various tests were carried on it including Marshall Stability test, Indirect Tensile Test, Rutting test and Skid resistance test. The rubber aggregates were used in different percentages with respect to the weight of the aggregates. Only the change was made in aggregates and not in the bitumen content which was kept constant at OBC. Throughout the study, the dry process of modification was employed. At every stage of mixing of crumb rubber aggregates, the separate optimum bitumen content was calculated, which was supported by the logic that there is a change in the materials in the bituminous concrete layer which will also alter the optimum bitumen content of the fresh aggregates. The replacement was done in variations like 0%, 2%, 4%, 6%, 8% and 10% of crumb rubber aggregates to the fresh aggregates. From the results of the Marshall Stability Test which was carried out at all percentage replacements, it suggests that at 4% of partial replacement the results were comparatively better than other percentage replacements. The study also shows improvement in Indirect Tensile Strength, Rutting or Permanent deformation and also in Skid Resistance. The study reveals it clearly that there is huge improvement in the permanent deformation of the bituminous concrete layer with the crumb rubber aggregates in it as compared to that of the normal bituminous concrete layer. The results of the different tests and the discussion is clearly given in the paper.

Crumb Rubber, Rubber Aggregates, Rutting strength, Indirect Tensile Strength, Skid Resistance, Optimum Binder content.

"Rubber Modified Asphalt Concrete Mix (RUMAC) ", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.5, Issue 12, page no.697-714, December 2018, Available :http://www.jetir.org/papers/JETIREB06086.pdf

"Rubber Modified Asphalt Concrete Mix (RUMAC) ", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.5, Issue 12, page no. pp697-714, December 2018, Available at : http://www.jetir.org/papers/JETIREB06086.pdf