The Application of Defoamer in Concrete

2024-05-29

In actual construction, the optimal air content range of concrete should be determined during the trial mixing process according to the location of the project and the functions of the concrete, and should be effectively controlled to help ensure the construction quality of concrete.

Before concrete is vibrated, there are a large number of bubbles inside it, mainly including air bubbles introduced during concrete mixing, transportation and blanking, bubbles introduced by water-reducing agents, and tiny bubbles introduced by air-entraining agents.

(1)Air bubbles introduced during concrete mixing, transportation and blanking.

(2)Bubbles introduced by water reducing agent.

(3)Bubbles introduced by air-entraining agents.

Defoamer help eliminate large air bubbles in concrete. On the one hand, adding defoamer can eliminate the bubbles between the concrete and the formwork to a certain extent, effectively prevent or eliminate the generation of honeycombs and pitted surfaces on the concrete surface, and make the surface of the concrete have higher smoothness and gloss. On the other hand, defoamer can eliminate a large number of bubbles inside concrete, reduce the air content and internal porosity of concrete, and improve the mechanical properties and durability of concrete. defoamer in concrete mainly eliminate bubbles introduced by water-reducing agents. Therefore, defoamer are often compounded with polycarboxylic acid-based water-reducing agents in projects to solve the problem of large air entrainment of polycarboxylic acid-based water-reducing agents.