摘要
利用再生砖粉取代工程水泥基复合材料(ECC)中的石英砂,制备再生砖粉ECC,采用混凝土快速冻融试验,研究了氯盐、硫酸盐及复合盐(氯盐+硫酸盐)溶液侵蚀作用下再生砖粉ECC的质量损失率和相对动弹性模量变化规律,建立了ECC在盐冻侵蚀环境下的损伤模型,并对其耐久性进行评价。结果表明:冻融循环300次后,再生砖粉ECC在清水、氯盐、硫酸盐及复合盐四种介质中的质量损失率分别为2.884%、4.984%、1.955%和6.891%,相对动弹性模量分别下降了6.468%、16.300%、24.303%和39.861%;再生砖粉ECC在单一盐冻情况下的抗冻等级大于F300,在复合盐冻情况下的抗冻等级大于F250,具有良好的抗盐冻性能;建立的冻融损伤模型可较好地反映ECC在不同冻融介质下的损伤度Dn与冻融循环次数的关系,可以为严寒地区的结构耐久性设计提供有效参考。
Recycled brick powder engineered cementitious composites(ECC)was prepared by replacing quartz sand in ECC with recycled brick powder.The mass loss rate and relative dynamic elastic modulus of recycled brick powder ECC under the erosion of NaCl solution,Na_(2)SO_(4)solution and NaCl+Na_(2)SO_(4)solution were studied by rapid freeze-thaw test of concrete.The damage model of ECC under salt frost erosion environment was established,and its durability was evaluated.The results show that after 300 freeze-thaw cycles,the mass loss rates of recycled brick powder ECC in water,NaCl salt solution,Na_(2)SO_(4)solution and NaCl+Na_(2)SO_(4)salt solution are 2.884%,4.984%,1.955%and 6.891%,respectively.The relative dynamic elastic modulus decreases by 6.468%,16.300%,24.303%and 39.861%,respectively.The frost resistance grade of recycled brick powder ECC is greater than F300 in the case of single salt-freezing,and the frost resistance grade is greater than F250 in the case of composite salt-freezing,which has good salt-freezing resistance.The established freeze-thaw damage model can better reflect the relationship between the damage degree D n of ECC under different freeze-thaw media and the number of freeze-thaw cycles,which can provide an effective reference for structural durability design in severe cold regions.
作者
楚留声
张鹏
赫约西
元成方
程站起
CHU Liusheng;ZHANG Peng;HE Yuexi;YUAN Chengfang;CHENG Zhanqi(School of Civil Engineering,Zhengzhou University,Zhengzhou 450001,China;Faculty of Architecture,Civil and Transportation Engineering,Beijing University of Technology,Beijing 100124,China)
出处
《硅酸盐通报》
CAS
北大核心
2024年第3期1012-1020,共9页
Bulletin of the Chinese Ceramic Society
基金
黄河实验室(郑州大学)一流课题专项基金资助项目(YRL22IR09)。
关键词
再生砖粉
工程水泥基复合材料
盐类侵蚀
冻融循环
质量损失率
相对动弹性模量
冻融损伤模型
recycled brick powder
engineered cementitious composite
salt erosion
freeze-thaw cycle
mass loss rate
relative dynamic elastic modulus
freeze-thaw damage model
