矿物掺合料与表面涂层对混凝土抗氯离子侵蚀能力的影响

Influence of Mineral Admixture and Coating on Chloride Resistance of Concrete

试验研究了矿物掺合料(不同掺量下单掺粉煤灰、矿渣或硅粉)、表面涂层材料(环氧树脂或聚合物水泥基防水材料)以及两者共同作用对混凝土抗氯离子侵蚀能力的影响。研究结果表明:矿物掺合料和表面涂层材料均可显著地提高混凝土的抗氯离子渗透能力;矿物掺合料的改善效果随着掺量的增加而增加,改善能力为硅粉>矿渣>粉煤灰;环氧树脂的作用效果比聚合物水泥基防水材料更明显;矿物掺合料与表面涂层结合使用效果更优。对混凝土抗氯离子渗透性能的作用机理分析表明:矿物掺合料的火山灰效应、填充效应和对氯离子的初始固化能力是改善混凝土的抗氯离子渗透性能的三个重要因素。

The influence of mineral admixture （single-added fly ash, slag or silica fume with different amount）, coatings （epoxy resin or water proof paint） and joint application of both on concrete＇s ability to resist chloride erosion is studied. The result shows that concrete ability to resist chloride ion penetration can be largely improved by mineral admixture or coatings; The chloride resistance of concrete increases with the increased amount of mineral admixture;The improving ability of silica fume is the best ,then the slag and fly ash is the last ;Epoxy resin is better than water-proof paint ; and joint application of both mineral admixture and coatings produces the best results. The mechanism of chloride ion penetration in concrete is analyzed and the result of the analysis indicates that the pozzolanic effect, packing effect and original capability of binding the chloride ion of mineral admixture are the important factors for the improvement of concrete＇s ability to resist chloride penetration.