关键词: 引气剂;混凝土;抗压强度;氯离子扩散系数;孔结构

Abstract: The change of concrete compressive strength,chloride diffusion coefficient and microstructure with different water-cement ratio and mixing dosage of air entrained agent (AEA)was investigated. The experimental results show that the bubble distributions and the continuity of the pores in the concrete are greatly affected by the amount of AEA in it. Appropriate amount of AEA in the concrete enhances the discontinuity of the pores and increases the amount of tiny bubbles which are independent,closed,stable and equally distributed,so that the resistance of chloride ion penetration is improved. The chloride diffusion coefficient of C30 concrete whose air content is 5% is 69 . 52% of that of the standard C30 concrete. And this effect to C50 concrete is more apparent than C30.

Key words: air-entrained agent (AEA );concrete;compressive strength;chloride diffusion coefficient;pore structure