DURABILITY UPGRADE OF CONCRETE STRUCTURES USING HYDROPHOBIC IMPREGNAUT

本文研究了硅烷对混凝土结构的影响。为了解硅烷憎水效果的长期稳定性，对混凝土小棱柱体进行了重量变化率和剥离深度的测定。此外，还对大截面混凝土不同深度处的相对湿度和温度进行了测试，以了解硅烷对混凝土结构实际尺寸的影响。所得试验结果被用来模拟混凝土中的水扩散。从这个项目中可以得出以下结论。(1)硅烷表面处理在一定程度上降低了碱集料反应膨胀。然而，活性集料和显着的氯离子混凝土可能会膨胀，即使硅烷处理。(2)当混凝土中氯离子含量较大时，硅烷表面处理会加速钢筋的腐蚀。硅烷处理不能减少钢的腐蚀。(3)有限元法可以模拟硅烷表面处理在混凝土截面中的有效深度。模拟和实验结果表明，硅烷处理后60天的有效深度为50 mm，180天的有效深度为200 mm。从180天到360天，有效深度没有增加，到目前为止为200 mm。硅烷表面处理对深度大于300 mm的混凝土区域没有任何影响。

In this study, effect of silane for concrete structures was investigeted. Weight change ratio and impregnauting depth of small concrete prisms were measured to know long term stability of silane hydorophobic effect. In addition, relative humidity and temparature at several depth of concrete of large section were measured so that effect of silane for actual scale of concrete structure could be made clear. Obtained test results were used to simulate water diffusion in concrete. Following conclusions may be drawn from this project.(1) Alkali-aggregate reaction expansion was reduced to some extent in a long term by silane surface treatment. However, concrete with reactive aggregate and significant chloride ion could expand even if treated by silane.(2) Corrosion of steel was accelarated by silane surface treatment if chloride ion was included in the concrete significantly. Silane treatment can not reduce steel corrosion.(3) Finite element method can simulate effective depth of silane surface treatment in concrete section. The simulation and experimental results indicated that the effective depth was 50mm in 60 days after silane treatment, and 200mm in 180 days. After 180 days upto 360 days, the effective depth did not increase and was 200mm so far. The concrete area deeper than 300mm was not given any influences by silane surface treatment.