DURABILITY UPGRADE OF CONCRETE STRUCTURES USING HYDROPHOBIC IMPREGNAUT

使用疏水性浸渍剂提升混凝土结构的耐久性

• 批准号: 07650529
• 负责人: MIYAGAWA Toyoaki
• 金额: $ 1.47万
• 依托单位: KYOTO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07650529/
• 关键词: HYDROPHOBIC IMPREGNAUT; CONCRETE STRUCTURES; DURABILITY; シラン; アルカリ骨材反応; 鉄筋腐食; 分子量

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.

在这项研究中，研究了硅烷对混凝土结构的影响。通过测量混凝土小棱柱的重量变化率和浸渍深度来了解硅烷疏水效果的长期稳定性。此外，还测量了大断面混凝土多个深度处的相对湿度和温度，以明确硅烷对混凝土结构实际尺寸的影响。获得的测试结果用于模拟混凝土中的水扩散。本课题可得出以下结论：(1)通过硅烷表面处理，从长远来看，一定程度上减少了碱骨料反应膨胀。然而，含有活性骨料和大量氯离子的混凝土即使经过硅烷处理也会发生膨胀。(2)如果混凝土中含有大量氯离子，硅烷表面处理会加速钢材的腐蚀。硅烷处理不能减少钢筋腐蚀。(3)有限元法可以模拟混凝土截面中硅烷表面处理的有效深度。模拟和实验结果表明，硅烷处理后60天有效深度为50mm，180天有效深度为200mm。 180天至360天后，有效深度没有增加，至今为200mm。硅烷表面处理对深度大于300mm的混凝土区域没有任何影响。