干湿循环和粉煤灰掺量对混凝土氯离子结合能力的影响

Influence of fly ash admixture and wet-dry times on chloride binding capacity of concrete

用自然扩散法测定了混凝土中的总氯离子和自由氯离子浓度,计算了粉煤灰混凝土氯离子结合能力,研究了粉煤灰掺量、干湿循环次数对混凝土氯离子结合能力的影响。结果表明:随粉煤灰掺量的增加,混凝土对氯离子的结合能力趋势是先升后降;混凝土的氯离子结合能力随干湿循环次数的增加而增大;粉煤灰掺量与干湿循环次数对混凝土氯离子结合能力是不存在耦合作用。因此,在盐湖地区的混凝土结构,建议选用掺加30%的粉煤灰混凝土。

The free chloride and total chloride of concretes were determined with natural diffusion method, the chloride binding capacity of fly ash concretes were computed, the influence of fly ash admixture content, wet-dry cycle times on the chloride binding capability of concreted.The results showed that with the increase of fly ash admixture content the chloride binding capacity of concrete increase at first and then decrease;the chloride binding capacity of concrete increase with the increase of wet-dry cycle times;the chloride binding capacity of concrete was not exist coupling between fly ash admixture content and wet-dry cycle times.Therefore, fly ash concrete with 30% fly ash content is recommended for concrete structure in salt lake area.