再生微粉对混凝土体积稳定性影响研究  

Study on the influence of recycled concrete powder on volume stability of concrete

作　　者：左俊卿 刘小艳[2] 姚武[3] 佘安明 房霆宸 朱敏涛 王磊[5] 袁靖 陈逸群 ZUO Junqing;LIU Xiaoyan;YAO Wu;SHE Anming;FANG Tingchen;ZHU Mintao;WANG Lei;YUAN Jing;CHEN Yiqun(Shanghai Construction Group Co.,Ltd.,Shanghai 200080,China;College of Mechanics and Materials,Hohai University,Nanjing 211100,China;Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education,Tongji University,Shanghai 201804,China;Shanghai Construction Building Materials Technology Group Co.,Ltd.,Shanghai 200086,China;College of Civil and Transportation Engineering,Guilin University of Technology,Guilin 541004,China;Suzhou Jianuo Environmental Engineering Co.,Ltd.,Suzhou 215200,China)

机构地区：[1]上海建工集团股份有限公司,上海200080 [2]河海大学力学与材料学院,江苏南京211100 [3]同济大学先进土木工程材料教育部重点实验室,上海201804 [4]上海建工建材科技集团股份有限公司,上海200086 [5]桂林理工大学土木与建筑工程学院,广西桂林541004 [6]苏州嘉诺环境科技股份有限公司,江苏苏州215200

出　　处：《混凝土》2024年第11期88-92,共5页Concrete

基　　金：国家重点研发计划项目(2019YFC1906200);上海市自然科学基金(21ZR1428100);江苏省科技计划项目(BE2022605);上海建工集团基础研究类项目(21JCYJ-11)。

摘　　要：采用混凝土平板开裂试验、干缩试验研究了再生微粉对混凝土体积稳定性影响,并结合扫描电镜分析了再生微粉对混凝土微观结构作用机理。试验结果表明:再生微粉掺合料能延缓混凝土开裂时间,减小开裂数量,降低混凝土开裂程度。混凝土平板开裂模式表现为离平板四周越近,裂缝分布越密集;离平板四周越远,裂缝越少,但长度越大。再生微粉能有效降低混凝土干燥收缩变形,这主要与再生微粉能密实混凝土微观结构,降低混凝土孔洞,提高水泥石与骨料界面接合度有关。The effect of recycled concrete powder on the volume stability of concrete was studied by using slab cracking test and dry shrinkage test,and the mechanism of recycled concrete powder on the microstructure of concrete was analyzed by scanning electron microscopy.The test results show that the recycled concrete powder admixture can delay the cracking time,reduce the cracking quantity and reduce the cracking degree of concrete.The cracking mode of concrete slab shows that the closer it is to the periphery of the slab,the more densely distributed the cracks are.The farther away from the sides of the slab,the fewer but the longer they cracks are.The recycled concrete powder can effectively reduce the dry shrinkage deformation of concrete,which is mainly related to the fact that the recycled concrete powder can compact the microstructure of concrete,reduce the pores of concrete,and improve the interface bonding degree of cement mortar and aggregate.

关 键 词：再生微粉 混凝土 开裂 收缩 微观结构 

分 类 号：TU528.041[建筑科学—建筑技术科学]