Author : Mohammed Safan, Fatma M. Eid and Mahmoud Awad

This paper evaluates the mechanical properties of rubberized concrete mixes containing rubber treated in sodium hydroxide solution and similar mixes containing untreated rubber the test results are compared to those control mixes without rubber. The aim of the present work is treating rubber to increase the bond between the rubber particles and concrete. Crumb rubber was utilized as partial replacement of sand in concrete. The replacement ratios were 5, 10 and 15% by volume of sand. Silica fume was used as an addition to increase the compressive strength. The water to cement ratio used in all concrete mixes was 0.42. The concentrations of the NaOH solution were 15%, 20% and 30%. It was found that using 20% concentration of NaOH for crumb rubber treatment was the most effective resulting in favourable hardened concrete characteristics. Experimental results showed higher compressive and flexural strengths, modulus of elasticity and tensile strength of rubberized concrete containing treated rubber compared to untreated rubber mixes. Although, there was a remarkable reduction in the strength and modulus of elasticity values with the increase in rubber content, using of fine rubber in building construction could help save energy, reduce costs and solve the solid waste disposal problem posed by this type of waste instead of negative effects on society and environment.

Keywords: Recycling, Tire rubber, Concrete, NaOH treatment

Article published in International Journal of Current Engineering and Technology, Vol.7, No.5 (Sept/Oct 2017)