摘要
为了研究再生砂超高性能混凝土(UHPC)的抗硫酸盐侵蚀性能,对掺再生砂和超细粉煤灰的超高性能混凝土进行了硫酸盐干湿循环侵蚀试验,测试了硫酸盐溶液侵蚀前后试件的抗压强度、相对动弹性模量、质量变化。通过离子滴定测定了不同侵蚀深度下硫酸根离子的分布,分析了再生砂和超细粉煤灰对硫酸根离子传输的影响。结果表明:经过90次硫酸盐干湿循环后,UHPC的耐侵蚀系数随着超细粉煤灰掺量的增加呈先增大后减小的趋势;超细粉煤灰掺量为20%(质量分数,下同)时,侵蚀全过程中UHPC的耐侵蚀系数、相对动弹性模量最大,硫酸根离子含量较低;再生砂掺量为50%时,UHPC在干湿循环45次之前的相对动弹性模量最大,相同深度下的硫酸根离子含量最低;复掺20%超细粉煤灰和50%再生砂的UHPC抗硫酸盐侵蚀性能最优。
A sulfate dry-wet cycle test was conducted on ultra-high performance concrete(UHPC)mixed with recycled sand and ultra-fine fly ash,in order to investigate the sulfate resistance of recycled sand UHPC.The compressive strength,relative dynamic elastic modulus and mass change of specimens before and after sulfate solution corrosion were tested.The effect of compounding recycled sand and ultra-fine fly ash on sulfate ion transport was analyzed by ion titration to determine the distribution of sulfate ions at different corrosion depths.The results show that the corrosion resistance coefficient of UHPC increases first and then decreases with the increase of ultra-fine fly ash content after 90 sulfate dry-wet cycles.When the content of ultra-fine fly ash is 20%(mass fraction,the same below),the corrosion resistance coefficient and relative dynamic elastic modulus of whole corrosion process are the largest,and the sulfate ion content is low.At 50%of recycled sand,UHPC has the highest relative dynamic elastic modulus before 45 dry-wet cycles,and the lowest sulfate ion content at the same depth.The UHPC compounded with 20%ultra-fine fly ash and 50%recycled sand has the best sulfate resistance.
作者
路宇
吴晨洁
王德志
赵晏
LU Yu;WU Chenjie;WANG Dezhi;ZHAO Yan(School of Civil and Hydraulic Engineering,Ningxia University,Yinchuan 750021,China;Water Resources Engineering Research Center in Modern Agriculture in Arid Regions,Yinchuan 750021,China;Ningxia Center for Research on Earthquake Protection and Disaster Mitigation in Civil Engineering,Yinchuan 750021,China;Engineering Technology Research Center of Water-Saving and Water Resource Regulation in Ningxia,Yinchuan 750021,China)
出处
《硅酸盐通报》
CAS
北大核心
2023年第10期3671-3678,共8页
Bulletin of the Chinese Ceramic Society
基金
宁夏自然科学基金(2023AAC03040)
宁夏重点研发计划(2022BEE03001)
国家自然科学基金(51968060)
宁夏青年拔尖人才培养工程(2080116)
宁夏一流学科项目(NXYLXK2021A03)。
关键词
超高性能混凝土
再生砂
超细粉煤灰
硫酸盐侵蚀
硫酸根离子含量
ultra-high performance concrete
recycled sand
ultra-fine fly ash
sulfate corrosion
sulfate ion content
