Water absorbing polymer balls as internal water curing agent in concrete to support hydration reaction

Abstract

polymer balls can supply water to the mortar or concrete mixture when added during the initial stage of mixing the concrete ingredients. It supplies the absorbed water during the hydration process of concrete as an internal water source. Water Absorption polymers (WAP) can absorb water up to hundred times of their own weight. Using this idea, the concrete mixture has been prepared with WAP and without WAP (Control) and subjected to air curing and water curing respectively. In this work WAP has been added in two different percentages i.e., 2.5% and 5% of the weight of cement, and the hardened concrete has been subjected to compression load. The mechanical strength and the volumetric change of these mixes were compared with the water cured control mix (Concrete without WAP). From the result, it was concluded that the air-cured specimen showed strength of 30.37 MPa and 28.74 MPa for 2.5% and 5% of addition of WAP balls respectively. This strength is about 99% and 94.2% of the strength of control water-cured specimen. Results also showed that specimens in air behave for expansion while samples in the water acted for shrinkage. Experiment results also showed that air-cured concrete specimens with WAP balls show significant strength gain over a period of 84 days compared to water-cured normal concrete mix samples.