干湿循环下机制砂粉煤灰混凝土的抗氯离子侵蚀性能  

Resistance of manufactured sand concrete with fly ash to chloride ion attack under dry-wet cycle

作　　者：延永东[1] 王鑫 陆春华[1] 陶松涛 季光前 YAN Yongdong;WANG Xin;LU Chunhua;TAO Songtao;JI Guangqian(Faculty of Civil Engineering and Mechanics,Jiangsu University,Zhenjiang,Jiangsu 212013,China)

机构地区：[1]江苏大学土木工程与力学学院,江苏镇江212013

出　　处：《江苏大学学报（自然科学版）》2023年第6期731-737,共7页Journal of Jiangsu University：Natural Science Edition

基　　金：国家自然科学基金资助项目(51878319,51608233)。

摘　　要：为了探讨干湿循环下机制砂混凝土内的氯离子传输规律,在不同的机制砂替代率、粉煤灰掺量和石粉质量分数条件下,开展干湿循环下的氯盐侵蚀试验,通过试验得到混凝土内的自由氯离子质量分数和氯离子扩散系数.结果表明:随机制砂替代率的增加,混凝土内的自由氯离子质量分数与氯离子扩散系数呈现先减小、后增大的趋势,机制砂替代率为50%机制砂混凝土的抗氯离子渗透性能最好;随着粉煤灰掺量的增大,机制砂混凝土抗氯离子渗透性能呈现先增强、后减弱的趋势,其中粉煤灰掺量为30%的机制砂混凝土能够最大程度抵抗氯离子的侵蚀;与不含石粉和石粉质量分数为11.6%的机制砂混凝土相比,石粉质量分数为5.8%混凝土的抗氯离子侵蚀性能最强;用适量的机制砂替代天然砂可以有效提高混凝土在氯盐溶液干湿循环下的耐久性寿命.To investigate the transportation mechanism of chloride ion in manufactured sand concrete(MSC),the chlorine salt erosion tests under dry-wet cycle were carried out under the conditions of different sand replacement rate,fly ash content and stone powder content.The mass fraction of free chloride ions and diffusion coefficient of chloride ions in concrete were obtained by the experiments.The results show that with the increasing of manufactured sand(MS)replacement,the chloride concentration at the same concrete depth and chloride diffusion coefficient of concrete is decreased with latter increasing.The concrete with 50%manufactured sand has the highest resistance performance to chloride ion penetration.With the increasing of fly ash content,the chloride penetration resistance of manufactured sand concrete is increased with latter decreasing.The manufactured sand concrete with 30%fly ash can resist the chloride penetration with the best effect.Compared with the MS without or containing 11.6%stone powder,the chloride ion erosion resistance of concrete with 5.8%stone power is the strongest.Proper amount of manufactured sand in concrete can improve the durability life of concrete in the dry-wet cycle of chloride solution.

关 键 词：机制砂混凝土 氯盐侵蚀试验 氯离子扩散系数 干湿循环 粉煤灰 石粉 

分 类 号：TU528[建筑科学—建筑技术科学]