Quality Evaluation of Air Entraining Agent Based on Air Void Parameters of Fresh Concrete

Abstract

In order to evaluate the quality of air entraining agent quickly and effectively. Air void parameters of fresh concrete with different air entraining agents were studied by Air Void Analyzer (AVA). The spacing factor and durability index of hardened concrete were tested and the relationship between the surface tension of air entraining agent and frost resistance of concrete was compared. The results showed that, the quality of air entraining agent can be evaluated quickly and effectively by diameter distribution of air bubbles in fresh concrete and spacing factor of fresh concrete. AEA2 introduced much more big air bubbles into concrete which is bad for the frost resistance of concrete. The quality of AEA2 was the worst, so the durability index of hardened concrete was 58.7%. Quality of air entraining agent cannot be characterized by properties of air entraining agent, but air entraining ability can be characterized by surface tension of air entraining agent. Keywords: air entraining agent (AEA), air void parameter, fresh concrete