Effect of Vinsol Resin Air Entraining Agent on Strength and Durability of Concrete

Damage to reinforced concrete structures in cold environment is caused by freezing and thawing cycles which reduces durability of structures. In cold areas continuous freezing and thawing causes cracks to spread and weakens the concrete to the point of failure therefore frost damage is a contributing factor in the eventual rupture and erosion in concrete structures. In this experimental study mix proportion of Cement: Sand: Aggregate = 1: 0.42: 1.41 W/C ratio of 0.42 was used as reference sample. To this reference mix percentage of vinsol resin i. e. air entraining agent was increased from 0 % to 2.5 % by weight of cement. The freezing and thawing cycles were continued for 3days, 7days and 28days. The freezing was done at -15C 2 for 5 hrs while thawing was done at 25C 2 for 5 hrs. The compressive strength of cubes was compared at each percentage of AEA added before and after freeze thaw cycle after 3days, 7days and 28days. Also compressive strength of air entrained agent added sample was compared with reference samples for obtaining optimum dosage of vinsol air entraining agent for reference mix. It was found slump value increased with the increment of the air entraining agent, making concrete more workable. There was a sharp increase in strength after 3 days due to rapid increase in the hydration reaction; initially the hydration reaction rate was slow by the freezing of the water molecules.1 to 1.5 % of vinsol resin air entraining agent is effective for producing frost resistance concrete at this mix proportion.