摘要
以非稳态氯离子迁移系数(D值)为指标,研究了复掺粉煤灰和矿粉的混凝土抗氯离子渗透性能及其时变规律。结果表明:降低水胶比,延长龄期(180 d以内)都能使混凝土的抗氯离子渗透性能增强;一定范围内,抗氯离子渗透性能均随矿粉掺量的增加而增加,随粉煤灰掺量的增加而降低,当矿粉掺量分别为37.5%、31.9%时,C30、C45混凝土的抗氯离子渗透性能最佳;随着龄期延长,C30、C45混凝土的D值差距增大;C30、C45混凝土在90 d、180 d的D值与粉煤灰、矿粉掺量之间的定量关系可用线性公式来表达;C30、C45混凝土的D值与龄期之间的定量关系可用基于Fick第二定律的幂函数表达,其中,指数a与粉煤灰掺量的关系可用高次多项式来表达。
The resistance to chloride ion penetration and its time-dependent law of the concrete mixed with fly ash and slag powder were studied with the non-steady state chloride ion migration coefficient(D value)as index.The results show that the resistance to chloride ion penetration of concrete can be enhanced by reducing the water-binder ratio and extending the age(within 180 d).The resistance to chloride ion penetration increases with the increase of slag powder content and decreases with the increase of fly ash content.In certain extent,when the ratio of slag powder content to the total cementitious material reaches 37.5%and 31.9%,the resistance to chloride ion penetration of C30 and C45 concrete reaches the best.With the increase of age,the difference in D values of C30,C45 concrete will increase.Quantitative relationship between the D values of C30,C45 concrete at 90 d,180 d age and the proportion of fly ash,slag powder in the total mass of the cementitious materials can be expressed by a linear formula.Quantitative relationship between the D values of C30 and C45 concrete and the age can be expressed by a power function based on the Fick’s second law.Relationship between the exponent a of the power function and the proportion of fly ash in the total mass of the cementitious materials can be expressed by a high-order polynomial.
作者
王艺霖
王顺尧
刘巧玲
李广宁
WANG Yi-lin;WANG Shun-yao;LIU Qiao-ling;LI Guang-ning(School of Civil Engineering,Shandong Jianzhu University,Key Laboratory of Building Structural Retrofitting and Underground Space Engineering of Ministry of Education,Jinan 250101,China)
出处
《混凝土与水泥制品》
2021年第5期1-5,共5页
China Concrete and Cement Products
基金
国家自然科学基金项目(51608311)
教育部“长江学者和创新团队发展计划”项目(IRT13075)
江苏省土木工程材料重点实验室开放基金项目(CM2016-07)。
关键词
粉煤灰
矿粉
氯离子
渗透性
时变
Fly ash
Slag powder
Chloride
Permeability
Time-dependent
