超高掺粉煤灰混凝土早龄期自生收缩研究  

Autogenous shrinkage of ultra-high volume fly ash concrete at early ages

作　　者：赵志方[1,2] 章斌 李超 ZHAO Zhifang;ZHANG Bin;LI Chao(College of Civil Engineering and Architecture,Zhejiang University of Technology,Hangzhou 310023,China;Key Laboratory of Civil Engineering Structures&Disaster Prevention and Mitigation Technology of Zhejiang Province,Hangzhou 310023,China)

机构地区：[1]浙江工业大学建筑工程学院,浙江杭州310023 [2]浙江省工程结构与防灾减灾技术研究重点实验室,浙江杭州310023

出　　处：《浙江工业大学学报》2019年第5期548-552,共5页Journal of Zhejiang University of Technology

基　　金：国家自然科学基金资助项目(51879235,51479178)

摘　　要：在绝热模式和温度匹配模式两种温度历程养护模式下,采用温度-应力试验机对粉煤灰掺量为35%的基准混凝土和粉煤灰掺量为80%的超高掺量粉煤灰混凝土进行温度应力试验。基于成熟度理论,将实际龄期转化为等效龄期,并由试验测得的两种温度历程下的自由试件的应变值,获得混凝土早龄期热膨胀系数,进而分离出自生收缩应变。提出两种混凝土的自生收缩发展模型,为预测超高掺粉煤灰混凝土的早龄期自生收缩变形提供依据。研究表明,超高掺粉煤灰混凝土的自生收缩发展比基准混凝土的小。A temperature-stress test of reference concrete with 35%fly ash(FA)content and ultra-high volume fly ash(UHVFA)concrete with 80%FA content under adiabatic and temperature match curing modes is carried out with a temperature-stress testing machine(TSTM).The actual age is converted into the equivalent one based on maturity theory.With the strains of free specimens tested on the TSTM under the two temperature history curing modes,the thermal expansion coefficient at early ages is obtained and the autogenous strain is separated from the total free one.The autogenous shrinkage mode of the two kinds of concretes is proposed.It provides a basis for predicting the autogenous shrinkage deformation of UHVFA at early ages.The results show that the autogenous shrinkage development of UHVFA concrete is lower than that of FA concrete.

关 键 词：温度-应力试验机 超高掺量粉煤灰混凝土 早龄期 等效龄期 自生收缩变形 

分 类 号：TU528[建筑科学—建筑技术科学]