摘要
本文通过混凝土吸水率、表面气体渗透系数、氯离子电通量及快速冻融循环试验,研究了引气剂对混凝土的抗渗及抗冻性能的影响,并从混凝土的孔结构及界面过渡区进行了微观机理分析。结果表明:随着引气剂掺量的增加,混凝土的抗压强度略有下降,混凝土的最终吸水率和氯离子电通量有减小的趋势,引气混凝土抗冻等级均达到了DF300。引气剂可以细化混凝土的孔结构,降低气泡间距系数,有利于改善混凝土的抗冻性和抗渗性。
This paper investigates the influence of air-entraining agent on the impermeability and frost resistance of concrete through the water absorption of concrete, surface gas permeability coefficient, chloride ion electric flux and fast freeze-thaw cycling test, and the pore structure and interfacial transition zone of concrete are also analyzed. The results show that the compressive strength of concrete shows a trend of decline with the increase of airentraining agent＇s dosage. With the increase of air content, the final water absorption rate and chloride ion electric flux of concrete have a tendency to decrease and airentraining concrete achieves the antifreeze level of DF300. Air-entraining agent can refine the pore structure of concrete, decrease the spacing factor of concrete which is conducive to improve the frost resistance and impermeability of concrete.
关键词
混凝土
渗透性
抗冻性
引气剂
孔结构
concrete
permeability
frost resistance
air entrainment agent
pore structure
