硅酸根电迁移反应法处理砂浆的耐久性

为提升砂浆的耐久性,用硅酸根电迁移反应法处理砂浆。通过对比试验,研究了基准砂浆、去除表面涂层的被处理砂浆、带有表面涂层的被处理砂浆试件的抗碳化、抗硫酸盐侵蚀、抗氯离子扩散和抗钢筋氯离子腐蚀的耐久性能。应用扫描电子显微镜(SEM)与压汞仪(MIP)研究了硅酸根电迁移反应法影响砂浆耐久性的微观作用机制。结果表明:砂浆试件的抗碳化、抗硫酸盐侵蚀、抗氯离子扩散与抗钢筋氯离子腐蚀的耐久性能由小到大的顺序为:基准砂浆、去除表面涂层的被处理砂浆试件、带有表面涂层的被处理砂浆试件;硅酸根电迁移反应法对耐久性的提升作用缘于它能致密化砂浆并生成表面涂层的双重效果;由于生成的表面涂层较薄,且含有众多微米级孔隙,使表面涂层对砂浆耐久性影响减弱,砂浆致密化在耐久性的提升中起主要作用。

Durabilities of mortar treated with method of electro-migration reaction of silicate ion

In order to improve the durability of mortar, the method of electro-migration reaction of silicate ion was used to treat mortar. Through comparison tests, the durabilities of different mortar specimens, including a control mortar specimen, a treated mortar specimen without surface coating, and a treated mortar specimen with surface coating, in resisting carbonization, sulfate attack, chloride diffusion, and corrosion of rebar by chloride ions were investigated. The microcosmic mechanism of the effects of this method on the durabilities of mortar was analyzed using a scanning electron microscope (SEM) and a mercury intrusion porosimeter (MIP). The results indicate that the durabilities of the mortar specimens in resisting carbonization, sulfate attack, chloride diffusion, and corrosion of rebar by chloride ions can be sequenced from low to high in the following order: control specimen, treated specimen without coating, and treated specimen with coating. The effect of the method of electro-migration reaction of silicate ion in improving the durability is due to its contribution in production of surface coating and mortar densification. Compared with densification of mortar, the produced coating has a relatively smaller effect on the improvement of durability due to its low thickness and numerous micron-grade pores.