超低温下水泥砂浆和石材热膨胀系数测定与分析
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摘要
超低温下混凝土骨料之间因热膨胀系数差异而产生的力势必会对结构产生影响,在结构设计中需要加以考虑。本研究在超低温环境下采用电阻应变计测试技术对水泥砂浆和石材两种材料热膨胀系数进行测量,得出其平均线膨胀系数随温度的变化规律。对比分析两种相互垂直取样方向对水泥砂浆和石材热膨胀系数的影响。研究结果表明:水泥砂浆和石材热膨胀系数随着温度的降低有着相似的变化规律,随温度的降低而减小;水泥砂浆和石材相互垂直取样方向上的热膨胀系数差异较大,说明在超低温下其热膨胀系数是各向异性的。实验得到水泥砂浆和石材在不同温度下的热膨胀系数值,为LNG储罐设计提供实验依据。
The force generated by the difference of thermal expansion coefficient between concrete aggregates will inevitably affect the structure at cryogenic temperatures,which needs to be taken into consideration in structural design. The coefficient of thermal expansion values of two kinds of materials,cement mortar and stone,were measured by the resistance strain gauge testing technology at cryogenic temperatures,and the relationship between mean linear expansion coefficient and temperature was obtained. The influence of sampling directions in this study was considered. The test results show that the coefficient of thermal expansion values of cement mortar and stone have a similar change rule,which decrease with the decrease of temperature. The sampling directions have a great effect on coefficient of thermal expansion values,which illustrate the coefficient of thermal expansion of cement mortar and stone is anisotropic at cryogenic temperatures. The coefficient of thermal expansion of cement mortar and stone at different temperatures is obtained,providing experimental basis for the design of LNG storage tank.
The force generated by the difference of thermal expansion coefficient between concrete aggregates will inevitably affect the structure at cryogenic temperatures,which needs to be taken into consideration in structural design. The coefficient of thermal expansion values of two kinds of materials,cement mortar and stone,were measured by the resistance strain gauge testing technology at cryogenic temperatures,and the relationship between mean linear expansion coefficient and temperature was obtained. The influence of sampling directions in this study was considered. The test results show that the coefficient of thermal expansion values of cement mortar and stone have a similar change rule,which decrease with the decrease of temperature. The sampling directions have a great effect on coefficient of thermal expansion values,which illustrate the coefficient of thermal expansion of cement mortar and stone is anisotropic at cryogenic temperatures. The coefficient of thermal expansion of cement mortar and stone at different temperatures is obtained,providing experimental basis for the design of LNG storage tank.
引文
[1]Kogbara R B,Iyengar S R,Grasley Z C,et al.A review of concrete properties at cryogenic temperatures:towards direct LNG containment[J].Constr.Build.Mater.,2013,47:760-770.
[2]Dahmani L,Khenane A,Kaci S.Behavior of the reinforced concrete at cryogenic temperatures[J].Cryogenics,2007,47:517-525.
[3]Gillard M N T.Liquefied natural gas tank analysis:cryogenic temperatures and seismic loading[J].Proc ICE-Eng Comput Mech,2012,165(1):49-56.
[4]水中和,曹蓓蓓.水泥混凝土材料热膨胀性能研究[C].广州:第九届全国水泥和混凝土化学及应用技术年会,2005,9:429-435.
[5]Marshall A L.Cryogenic concrete[J].Cryogenics,1982,11:555-565.
[6]Krstulovic-Opara N.Liquefied natural gas storage:material behavior of concrete at cryogenic temperatures[J].ACI Mater.J.,2007,104:297-306.
[7]ACI.376-11.Code requirements for design and construction of concrete structures for the containment of refrigerated liquefied gases and commentary[S].An ACI Standard Farmington Hills,MI:American Concrete Institute,2011.
[8]Kogbara R B,Iyengar S R,Grasley Z C,et al.Correlation between thermal deformation and microcracking in concrete during cryogenic cooling[J].NDT&E International,2016,77:1-10.
[9]9%nickel steel:for use at cryogenic temperatures[M].USA:Arcelor Mittal,2010.
[10]钱春香,朱晨峰.骨料粒径对混凝土热膨胀性能的影响[J].硅酸盐学报,2009,37(1):18-22.
[11]江晨晖,杨杨,李鹏,等.水泥砂浆的早龄期热膨胀系数的时变特征[J].硅酸盐学报,2013,41(5):605-611.
[12]Siddiqui M S,Grasley Z C,Fowler D W.Internal water pressure development in saturated concrete cylinder subjected to coefficient of thermal expansion tests:Poroelastic model[J].Constr.Build.Mater.,2016,112:996-1004.
[13]张研,陈海燕,张子明,等.基于细观尺度的混凝土热膨胀性能研究[J].建筑材料学报,2011,14(3):310-316.
[14]姚武,郑欣.配合比参数对混凝土热膨胀系数的影响[J].同济大学学报(自然科学版),2007,35(1):77-81.
[15]李燕勇.几种材料大试样低温膨胀系数测试及研究[J].低温与超导,1996,24(1):49-52.
[16]顾琢如.玻璃低温膨胀系数的测定[J].光学机械,1980(5):44-48.
[2]Dahmani L,Khenane A,Kaci S.Behavior of the reinforced concrete at cryogenic temperatures[J].Cryogenics,2007,47:517-525.
[3]Gillard M N T.Liquefied natural gas tank analysis:cryogenic temperatures and seismic loading[J].Proc ICE-Eng Comput Mech,2012,165(1):49-56.
[4]水中和,曹蓓蓓.水泥混凝土材料热膨胀性能研究[C].广州:第九届全国水泥和混凝土化学及应用技术年会,2005,9:429-435.
[5]Marshall A L.Cryogenic concrete[J].Cryogenics,1982,11:555-565.
[6]Krstulovic-Opara N.Liquefied natural gas storage:material behavior of concrete at cryogenic temperatures[J].ACI Mater.J.,2007,104:297-306.
[7]ACI.376-11.Code requirements for design and construction of concrete structures for the containment of refrigerated liquefied gases and commentary[S].An ACI Standard Farmington Hills,MI:American Concrete Institute,2011.
[8]Kogbara R B,Iyengar S R,Grasley Z C,et al.Correlation between thermal deformation and microcracking in concrete during cryogenic cooling[J].NDT&E International,2016,77:1-10.
[9]9%nickel steel:for use at cryogenic temperatures[M].USA:Arcelor Mittal,2010.
[10]钱春香,朱晨峰.骨料粒径对混凝土热膨胀性能的影响[J].硅酸盐学报,2009,37(1):18-22.
[11]江晨晖,杨杨,李鹏,等.水泥砂浆的早龄期热膨胀系数的时变特征[J].硅酸盐学报,2013,41(5):605-611.
[12]Siddiqui M S,Grasley Z C,Fowler D W.Internal water pressure development in saturated concrete cylinder subjected to coefficient of thermal expansion tests:Poroelastic model[J].Constr.Build.Mater.,2016,112:996-1004.
[13]张研,陈海燕,张子明,等.基于细观尺度的混凝土热膨胀性能研究[J].建筑材料学报,2011,14(3):310-316.
[14]姚武,郑欣.配合比参数对混凝土热膨胀系数的影响[J].同济大学学报(自然科学版),2007,35(1):77-81.
[15]李燕勇.几种材料大试样低温膨胀系数测试及研究[J].低温与超导,1996,24(1):49-52.
[16]顾琢如.玻璃低温膨胀系数的测定[J].光学机械,1980(5):44-48.