引气混凝土的抗碳化性能研究

分别研究了不同浆骨比、含气量和水胶比情况下,掺入粉煤灰后高耐久性混凝土的抗碳化性能和抗氯离子渗透性能。研究结果表明:碳化深度随粉煤灰掺量的增加而增大;氯离子扩散系数随粉煤灰掺量的增加而减小,当粉煤灰掺量超过一定掺量时氯离子扩散系数又随粉煤灰掺量的增加而增加。碳化深度、氯离子扩散系数随含气量增加而减小,而当含气量大于4%时,碳化深度、氯离子扩散系数又随含气量的增加而增大;碳化深度、氯离子扩散系数随浆骨比(32.5/67.5至37.5/62.5)的增大而增大;水胶比越小的抗碳化性能越好、氯离子扩散系数越小。

Experimental Study on Carbonization Resistance of Air-Entraining Concrete

Carbonization resistance of concrete with fly ash still has many different points.Carbonization resistance and chloride ion impermeability of high durability concrete with fly ash are studied in this paper,include different paste-total aggregate ratio,air content and water-binder ratio.The results show that concrete carbonation depth increases with the improvement of fly ash amount,but diffusion coefficient of chloride ion is contrary.When fly ash amount exceeds certain value,the chloride ion diffusion coefficient increases with fly ash dosage.Carbonation depth and diffusion coefficient decrease with improvement of concrete air content,but the result is opposite when the air content is greater than 4 percent.The depth of carbonation and chloride ion diffusion coefficient increase with paste-total aggregate ratio from 32.5/67.5 to 37.5/62.5.The water/binder ratio decreases,the depth of carbonation and diffusion coefficient turn smaller and smaller.