大掺量粉煤灰混凝土早龄期拉伸徐变特性研究  

Study on tensile creep characteristics of high volumefly ash concrete at early ages

作　　者：马成畅[1,2] 徐斐熙 杨杨 姚冀恺[1] 倪彤元 陈春心 姚水丰[1] MA Chengchang;XU Feixi;YANG Yang;YAO Jikai;NI Tongyuan;CHEN Chunxin;YAO Shuifeng(College of Civil Engineering,Zhejiang University of Technology,Hangzhou 310023,China;Key Laboratory of Civil EngineeringStructures&Disaster Prevention and Mitigation Technology of Zhejiang Province,Hangzhou 310023,China;Zhejiang Xinchang Traffic Engineering Management Center,Zhejiang Xinchang 312599,China)

机构地区：[1]浙江工业大学土木工程学院,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 [3]浙江省新昌县交通工程管理中心,浙江新昌312599

出　　处：《浙江工业大学学报》2023年第2期131-138,共8页Journal of Zhejiang University of Technology

基　　金：国家自然科学基金资助项目(51778583);浙江省重点研发计划项目(2021C01060);浙江省教育厅科研项目(Y202043148)。

摘　　要：为探究粉煤灰掺量和加载龄期对早龄期混凝土拉伸徐变的影响规律,在应力强度比为0.4的条件下,实验研究了不同粉煤灰掺量(0%,30%,60%)和不同加载龄期(3,7,14,28 d)下的拉伸徐变特性。研究结果表明:混凝土拉伸徐变随着加载龄期的推迟而递减;混凝土拉伸徐变速度在持荷初期(0~3 d)随着加载龄期的推迟呈指数规律下降,在持荷中后期(3 d后)加载龄期影响逐渐减小;在同一加载龄期,混凝土拉伸徐变随粉煤灰占比的提高而增大。拉伸徐变随强度增长呈指数规律递减,该规律在60%粉煤灰掺量的混凝土中更为显著。In order to explore the influence of fly ash content(0%,30%and 60%)and loading age(3,7,14 and 28 days)on the tensile creep of early age concrete,the tensile creep characteristics of high volume fly ash concrete with a water-binder ratio of 0.4 are studied experimentally under a stress to strength ratio of 0.4.The results show that the tensile creep of concrete decreases with the delay of loading age.The tensile creep rate decreases exponentially with the delay of loading age at the initial stage of load holding(0-3 days)and the influence of loading age slows down in the middle and late stages of load holding(after 3 days).The tensile creep of concrete increases with the increase of fly ash content at a given loading age.The tensile creep decreases exponentially with the increase of strength,which is more significant for concrete with 60%fly ash content.

关 键 词：粉煤灰 混凝土 拉伸徐变 早龄期 加载龄期 

分 类 号：TU528[建筑科学—建筑技术科学]