针对一种严酷环境全耐久要求的混凝土,在复掺粉煤灰和矿渣微粉的基础上,对比研究掺加硅灰、引气剂、钢纤维对高强混凝土性能的影响;制备出了一种具有较好的流动性,强度等级为C60且具有一定抗拉性能的全耐久混凝土。采用真空保水法、X—CT、压汞法三种方法测得混凝土孔隙率,研究了该混凝土的各种耐久性及其相互关系。结果表明,不同测孔方法,采用不同方法评估混凝土的渗透性,其测试结果差别较大;高强混凝土引气后,收缩增大,抗渗性与强度降低,对其他耐久性无影响。
Focusing on a kind of full durability concrete in harsh environment, based on the compound of fly ash and GGBFS, the influence of mixing with silica fume, air entraining agent and steel fiber on the property of high strength concrete was studied, and concrete with better fluidity, strength level of C60 and certain tensile property was prepared. The concrete porosity was studied by applying vacuum water conservation method, X-CT and mercury porosimeter, and various concrete durability and its relative relationships were studied. The results indicate that when different hole measurement methods were applied to evaluate the concrete permeability, there is a large difference among the results. After using air entraining agent in the high strength concrete, there appears an increase in shrinkage property and a decrease in permeability and strength properties, while there is no impact on other durable properties.