Optimum Superplasticizer Added to Concrete Containing Waste Crumb Rubber

Abstract

Rubberized concrete was produced by replacements 10% of sand by 1 mm waste crumb rubber. Rubberized concrete with 0.25%, 0.5%, 0.75% and 1.0% superplasticizer contents were prepared without change the water-cement ratio purposely to study the effects of superplasticizer to the rubberized concrete. Several tests were carried out to study the effect of superplasticizer such as slump test, compression test, split tensile test, flexural test and ultrasonic pulse velocity test. The results show that an increase of superplasticizer will increase the workability of the concrete without changing the water-cement ratio. It was found that the rubberized concrete with content 0.75% superplasticizer produced better compressive strength, split tensile strength, flexural strengthd ultrasonic pulse velocity.

Keywords: Crumb rubber, Superplasticizer, Workability, Concrete strength.