Effect of superplasticizer on the Compressive strength of concrete

Abstract

The effect of superplasticizer (Polycarboxylic Ether) on the compressive strength of concrete using different water cement ratio was studied. The superplasticizer was used as an admixture. The superplasticizer was added to the concrete at 0%, 2%, 2.5% and 3.5% by weight of cement and varying water cement ratio of 0.4, 0.45, 0.50 and 0.55. Sixty-four (64) concrete cubes were cast and cured for 7, 14, 21 and 28 days respectively. At the end of each hydration period, the cubes were crushed and their compressive strength was determined. The compressive strength of 0- 3.5% level of superplasticizer at water cement ratio of 0.4 – 0.55 ranged from 11.38 – 18.04N/mm² at 7days curing, while the compressive strength at the same percentage level of superplasticizer and water-cement ratio at 14 days curing ranged from 12.78 – 18.80N/mm². The compressive strength of 0-3.5% level of superplasticizer at water cement ratio of 0.4 – 0.55 ranged from 14.00 – 21.90N/mm² and 15.00 – 23.10N/mm² for 21 and 28 days curing respectively. The slump test of 0-3.5% level of superplasticizer at 0.4 – 0.55 water-cement ratio ranged from 10-90mm.

Keywords: Superplasticizer, concrete, water-cement ratio

International Journal of Natural and Applied Sciences, 7(1): 37 - 40, 2011 ISSN: 0794 – 4713