摘要: |
使用ASTM C1202(混凝土抗氯离子渗透能力),RCM(快速氯离子迁移)和ACR(交流电阻率)3种抗氯离子渗透能力测试方法,研究了水胶比(质量比)022~062,空白和掺入矿物掺合料(粉煤灰和硅灰)混凝土的抗氯离子渗透能力.分析了3种方法测试结果的相关性,以及水胶比、矿物掺合料和龄期对混凝土抗压强度和抗氯离子渗透能力的影响.结果表明: 3种方法的测试结果具有一定的相关性: ASTM C1202和RCM的测试结果呈分段线性关系,ASTM C1202和ACR的测试结果呈双曲线关系3种方法均有各自的适用范围,因此,在评价混凝土抗氯离子渗透能力时,应选择适宜的测试方法.掺入粉煤灰可降低早龄期但提高长龄期混凝土的抗氯离子渗透能力;复合掺入粉煤灰和硅灰可提高早龄期混凝土抗氯离子渗透能力,在长龄期其作用效果尤为显著.混凝土抗氯离子渗透能力和抗压强度之间无简单的线性关系. |
关键词: 混凝土 水胶比 粉煤灰 硅灰 抗氯离子渗透能力 ASTM C1202 快速氯离子迁移(RCM) 交流电阻率(ACR) |
DOI:103969/j.issn1007 9629201504029 |
分类号: |
基金项目:“十一五”国家科技支撑计划项目(2011BAG07B04) |
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Adaptability of the Evaluation Methods of Concrete |
Anti chloride Penetration AbilityHAN Jianguo, LI Kefei
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Department of Civil Engineering, Tsinghua University, Beijing 100084, China
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Abstract: |
Using evaluation methods of ASTM C1202(concretes ability to resist chloride ion penetration), RCM(rapid chloride migration) and ACR(alternative current resistivity), concretes with different water to binder ratios (022 to 062) and mineral admixtures (fly ash and silica fume) were evaluated for their anti chloride penetration ability. Results of the aforementioned three evaluation methods were compared. Influences of water to binder ratio, mineral admixture, curing age on concrete strength and anti chloride penetration ability were analyzed. Results from the three different evaluation methods are correlated. There is linear correlation between results of ASTM C1202 and RCM at different regions, while hyperbola correlation exists between results of ASTM C1202 and ACR. Each evaluation method has its application region, and appropriate evaluation method should be adopted when evaluation the anti chloride penetration ability of concrete. Meanwhile, fly ash can reduce anti chloride penetration ability of concrete at early age but enhance it at long age; the combination of fly ash and silica fume can significantly enhance anti chloride penetration ability of concrete, especially at long age. No linear relationship exists between anti chloride penetration ability and compressive strength of concrete. |
Key words: concrete water to binder ratio fly ash silica fume anti chloride penetration ability ASTM C1202 rapid chloride migration(RCM) alternative current resistivity(ACR) |