工程温度条件下氧化镁膨胀剂对混凝土性能的影响
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摘要
为进一步促进掺氧化镁混凝土的研究与应用,研究了工程温度条件下氧化镁膨胀剂的活性和掺量对混凝土力学性能和变形性能的影响。结果表明:同等条件下,氧化镁活性越高,掺量越大,混凝土强度下降越明显;掺氧化镁膨胀剂的混凝土对养护温度的变化非常敏感,工程温度条件使混凝土强度增长迅速;氧化镁掺量越大,混凝土的膨胀值越大;氧化镁活性值越高,膨胀开始的龄期越短。
In order to improve studies and application of concrete with light-burned magnesium oxide(Mg O concrete),the influence of the chemical activities and the mixing content of Mg O expansive agents on the mechanical properties and deformation properties of the concrete under the condition of engineering temperature were studied.The experimental results show that,under the same conditions,the higher the activity and the larger the content of magnesium oxide,the more obvious the decrease of concrete strength.The concrete with magnesium oxide expansive agent is very sensitive to the change of curing temperature,and the engineering temperature conditions make the concrete strength increase rapidly.The larger the content of magnesium oxide,the larger the expansion value of the concrete.The higher the activity of magnesium oxide,the earlier the expansion begins.
In order to improve studies and application of concrete with light-burned magnesium oxide(Mg O concrete),the influence of the chemical activities and the mixing content of Mg O expansive agents on the mechanical properties and deformation properties of the concrete under the condition of engineering temperature were studied.The experimental results show that,under the same conditions,the higher the activity and the larger the content of magnesium oxide,the more obvious the decrease of concrete strength.The concrete with magnesium oxide expansive agent is very sensitive to the change of curing temperature,and the engineering temperature conditions make the concrete strength increase rapidly.The larger the content of magnesium oxide,the larger the expansion value of the concrete.The higher the activity of magnesium oxide,the earlier the expansion begins.
引文
[1]MO L,DENG M,TANG M,et al.MgO expansive cement and concrete in China:Past,present and future[J].Cement and Concrete Research,2014,57(3):1-12.
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[3]尚荣朝.轻烧MgO膨胀剂对寒冻地区水工混凝土耐久性影响的试验[J].混凝土,2017(4):91-98.
[4]宋诗琦,蒋林华,姜少博,等.养护方式对纳米氧化镁水泥浆体强度的影响研究[J].混凝土,2017(9):40-44.
[5]刘加平,王育江,田倩,等.轻烧氧化镁膨胀剂膨胀性能的温度敏感性及其机理分析[J].东南大学学报,2011,41(2):359-364.
[6]YE Q,YU K,ZHANG Z.Expansion of ordinary portland cement paste varied with nano-MgO[J].Construction and Building Materials,2015(78):189-193.
[7]陈昌礼,赵振华,李维维,等.长龄期外掺氧化镁混凝土自生体积变形分析[J].水利水运工程学报,2015(5):54-59.
[8]曹丰泽,阎培渝.活性与养护温度对氧化镁膨胀剂膨胀性能的影响[J].硅酸盐学报,2017,45(8):1088-1095.
[9]高培伟,卢小琳,唐明述.膨胀剂对混凝土变形性能的影响[J].南京航空航天大学学报,2006,38(2):251-255.
[2]NAGATAKI S,GOMI H.Expansive admixtures(mainly ettringite)[J].Cement and Concrete Composites,1998,20(2-3):163-170.
[3]尚荣朝.轻烧MgO膨胀剂对寒冻地区水工混凝土耐久性影响的试验[J].混凝土,2017(4):91-98.
[4]宋诗琦,蒋林华,姜少博,等.养护方式对纳米氧化镁水泥浆体强度的影响研究[J].混凝土,2017(9):40-44.
[5]刘加平,王育江,田倩,等.轻烧氧化镁膨胀剂膨胀性能的温度敏感性及其机理分析[J].东南大学学报,2011,41(2):359-364.
[6]YE Q,YU K,ZHANG Z.Expansion of ordinary portland cement paste varied with nano-MgO[J].Construction and Building Materials,2015(78):189-193.
[7]陈昌礼,赵振华,李维维,等.长龄期外掺氧化镁混凝土自生体积变形分析[J].水利水运工程学报,2015(5):54-59.
[8]曹丰泽,阎培渝.活性与养护温度对氧化镁膨胀剂膨胀性能的影响[J].硅酸盐学报,2017,45(8):1088-1095.
[9]高培伟,卢小琳,唐明述.膨胀剂对混凝土变形性能的影响[J].南京航空航天大学学报,2006,38(2):251-255.