不同超低温温度区间冻融循环作用混凝土弹性模量软化性能试验研究
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  • 英文篇名:EXPERIMENTAL STUDY ON ELASTIC MODULUS OF CONCRETE UNDERGOING FREEZE-THAW CYCLE ACTION WITH DIFFERENT ULTRALOW TEMPERATURE RANGES
  • 作者:时旭东 ; 李亚强 ; 钱磊 ; 李俊林 ; 汪文强
  • 英文作者:SHI Xu-dong;LI Ya-qiang;QIAN Lei;LI Jun-lin;WANG Wen-qiang;Department of Civil Engineering, Tsinghua University;
  • 关键词:混凝土 ; 超低温 ; 冻融循环作用 ; 温度区间 ; 弹性模量
  • 英文关键词:concrete;;ultralow temperature;;freeze-thaw cycle action;;temperature range;;elastic modulus
  • 中文刊名:GCLX
  • 英文刊名:Engineering Mechanics
  • 机构:清华大学土木工程系;
  • 出版日期:2019-08-13
  • 出版单位:工程力学
  • 年:2019
  • 期:v.36
  • 基金:国家自然科学基金项目(51478242,51878375)
  • 语种:中文;
  • 页:GCLX201908011
  • 页数:9
  • CN:08
  • ISSN:11-2595/O3
  • 分类号:109-116+143
摘要
通过混凝土经历10℃~-40℃、10℃~-80℃和10℃~-160℃等3种典型的超低温温度区间冻融循环作用试验,探讨不同的温度区间和冻融循环作用次数对混凝土弹性模量的影响。结果表明,随冻融循环作用次数的增加,上限温度时因冻融损伤累积使混凝土的弹性模量呈逐渐软化趋势,其中下限温度较低温度区间的变化趋势最为明显;下限温度时因混凝土内孔隙水结冰使混凝土弹性模量呈先增大后减小趋势,且较上限温度时的变化幅度更大。不同温度区间的混凝土相对弹性模量差以及上下限温度时单次冻融软化指标和累积冻融软化指标均存在明显的差异且变化规律较为复杂。该文还由试验结果拟合出混凝土相对弹性模量与超低温冻融循环作用的温度区间和次数间的关系式。所获得的这些结果可为LNG储罐类混凝土结构的设计和安全性能评估提供参考。
        Through experiments of concrete experiencing freeze-thaw cycle action with three typical ultralow temperature ranges of 10℃~-40℃, 10℃~-80℃ and 10℃~-160℃, the effects of different temperature ranges and freeze-thaw cycles on concrete elastic modulus are investigated. The test results show that with increase in the freeze-thaw action cycles the concrete elastic moduli at upper limit temperature are decreasing due to damage accumulation from freeze-thaw cycle action, and their changing trends are most obvious for the temperature range of which the lower limit temperature is lower; the concrete elastic moduli at lower limit temperature increases first due to freezing of the pore water inside concrete and then decreases with increase in the freeze-thaw action cycles,and their changing ranges are greater than those at the upper limit temperature. The concrete relative elastic modulus difference, single freeze-thaw softening index, and cumulative freeze-thaw softening index of concrete relative elastic modulus at upper and lower limit temperatures for different temperature ranges, are obviously different and their variation regularities are also more complex. The test results also reveal the relationship between the concrete relative elastic modulus and the factors of temperature range and freeze-thaw action cycles under ultralow temperature. These results can provide reference for the design and safety performance evaluation of the LNG storage tank.
引文
[1]张楠,李景芳,张志明,等.超低温环境混凝土研究与应用综述[J].混凝土,2012(12):27―29.Zhang Nan,Li Jingfang,Zhang Zhiming,et al.State-of-art review on research and application of concrete at very low temperature[J].Concrete,2012(12):27―29.(in Chinese)
    [2]Browne R D,Bamfourth P B.The use of concrete for cryogenic storage:A summary of research,past and present[C]//Concrete Soc Cryogenic Concrete:Proceedings of the1st International Conference.London:Construction Press,1982:135.
    [3]Kogbara R B,Iyengar S R,Grasley Z C,et al.A review of concrete properties at cryogenic temperatures:Towards direct LNG containment[J].Construction&Building Materials,2013,47(10):760―770.
    [4]Dahmani L,Khenane A,Kaci S.Behavior of the reinforced concrete at cryogenic temperatures[J].Cryogenics,2007,47(9):517―525.
    [5]Miura T.The properties of concrete at very low temperatures[J].Materials and Structures,1989,22(4):243―254.
    [6]Berner D E.Behavior of prestressed concrete subjected to low temperatures and cyclic loading[R].Berkeley(USA):California University,1984.
    [7]时旭东,马驰,张天申,等.不同强度等级混凝土-190℃时受压强度性能试验研究[J].工程力学,2017,34(3):61―67.Shi Xudong,Ma Chi,Zhang Tianshen,et al.Experimental study on compressive behavior of different strength grade concretes exposed-190℃[J].Engineering Mechanics,2017,34(3):61―67.(in Chinese)
    [8]时旭东,居易,郑建华,等.混凝土低温受压强度试验研究[J].建筑结构,2014(5):29―33.Shi Xudong,Ju Yi,Zheng Jianhua,et al.Experimental study on compressive strength of concrete exposed to cryogenic temperature[J].Building Structure,2014(5):29―33.(in Chinese)
    [9]吕超.混凝土给定超低温作用区间冻融性能试验研究[D].北京:清华大学,2015.Lv Chao.Experimental Study on Behavior of Concrete subjected to Freezing-thawing Action under Given Cryogenic[D].Beijing:Tsinghua University,2015.(in Chinese)
    [10]刘超.混凝土低温受力性能试验研究[D].北京:清华大学,2011.Liu Chao.Experimental investigation on mechanical property of concrete exposed to low temperature[D].Beijing:Tsinghua University,2011.(in Chinese)
    [11]时旭东,钱磊,马驰,等.经历常温降至-196℃再回温混凝土温度场试验研究[J].工程力学,2018,35(5):162―169.Shi Xudong,Qian Lei,Ma Chi,et al.Experimental study on temperature field of concrete during cooling from Room temperature to-196℃and then returning to Room temperature[J].Engineering Mechanics,2018,35(5):162―169.(in Chinese)
    [12]李俊林.不同低温温度区间混凝土冻融循环作用性能试验研究[D].北京:清华大学,2017.Li Junlin.Experimental study on concrete performance undergoing freeze-thaw cycles with different cryogenic temperature ranges[D].Beijing:Tsinghua University,2017.(in Chinese)

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