含粉煤灰微珠混凝土的强度和徐变特性研究  

Research on strength and creep characteristics of concrete containing fly ash microbead

作　　者：和文超 薛静 王伟[3] HE Wenchao;XUE Jing;WANG Wei(Department of Civil Engineering,Changzhi Vocational and Technical College,Changzhi 046000,China;College of Water Resources Science and Engineering,Taiyuan University of Technology,Taiyuan 030024,China;College of Civil Engineering,Taiyuan University of Technology,Taiyuan 030024,China)

机构地区：[1]长治职业技术学院土木工程系,山西长治046000 [2]太原理工大学水利科学与工程学院,山西太原030024 [3]太原理工大学土木工程学院,山西太原030024

出　　处：《无机盐工业》2023年第1期124-128,158,共6页Inorganic Chemicals Industry

基　　金：国家自然科学基金(51808375);山西省应用基础研究面上自然基金项目(201901D111040);山西省教育科学“十三五”规划教育政策研究专项课题(ZC-20053)。

摘　　要：利用粉煤灰微珠按10%、20%和30%(质量分数)部分替代水泥制备了混凝土试样,并对混凝土试样的抗压强度、弹性模量和徐变进行了测试,同时通过压汞孔隙率实验对试样的微观结构进行了研究。结果表明,粉煤灰微珠会使混凝土的早期抗压强度和弹性模量下降,但是对混凝土长期强度增长和弹性模量增长有明显的促进作用,在90 d时粉煤灰微珠掺量为20%的试样强度和弹性模量最高。掺入20%的粉煤灰微珠可以降低混凝土的比徐变,但是过多的粉煤灰微珠反而会增加混凝土的徐变变形。孔隙分析结果表明,总孔隙体积较高时,混凝土的强度较低,徐变变形较大;而加入20%粉煤灰微珠会降低混凝土的中孔隙、大孔隙和总孔隙体积,从而改善混凝土的强度和徐变特性。Concrete samples were prepared by partially replacing cement with fly ash microbeads at weight ratio of 10%,20% and 30%,and then the compressive strength,elastic modulus and creep of the concrete samples were tested.At the same time,the microstructure of the samples was studied by the mercury intrusion porosity test.The results showed that the fly ash microbeads would reduce the early age compressive strength and elastic modulus of concrete,but it showed significant promoting effect on the long-term strength growth and elastic modulus growth of concrete.At 90 d,the sample with fly ash microbead substitution ratio of 20% had the highest strength and elastic modulus.Adding 20% fly ash microbeads could reduce the specific creep of concrete,but too much fly ash microbeads would increase the creep deformation of concrete.The pore analysis results showed that when the total pore volume was higher,the strength was low and the creep deformation of concrete was large.The addition of 20% fly ash microbeads would reduce the mesopore,macropore and total pore volume of concrete,thereby improving the strength and creep characteristics of concrete.

关 键 词：混凝土 粉煤灰微珠 抗压强度 弹性模量 徐变 孔隙特征 

分 类 号：TQ536.4[化学工程—煤化学工程]