矿物掺合料对混凝土氯离子渗透扩散性研究

研究了不同种类、不同掺量的矿物掺合料对混凝土氯离子渗透性的影响，试验结果显示：单掺矿物掺合料（磨细粉煤灰、矿渣、硅灰）改善混凝土抗氯离子渗透能力，且改善效果硅灰最佳，磨细粉煤灰其次，矿渣最差。从机理上分析，矿物掺合料的火山灰效应改善了混凝土中水泥石与集料之间的薄弱界面，降低孔隙率，使孔细化，同时生成更多低碱度的C-S-H凝胶增加混凝土的Cl^-固化能力，从而提高了混凝土抗氯离子渗透能力。

Study on Influence of Mineral Admixture on Chloride Ion Penetration and Diffusion in Concrete

In this paper, the influences of different kinds and different amount of mineral admixture to Cl-penetration and diffusion in concrete are studied. The results of experiment show that separate addition of mineral admixture (ground fly ash, slag fines, silica fume) into concrete can improve its resistance to chloride ion penetration and diffusion. Furthermore,the effect of silica fume is the best, fly ash second, and then follows slag fines. Mechanism analysis shows that the pozzolanic effect of mineral admixture improves the interface between the cement and aggregate in concrete, reduces the total porosity, makes pores more smaller, on the other hand it increases the Cl-consolidation capability of concrete with low alkaline C-S-H gel produced. So the resistance to chloride ion penetration of concrete is improved.