摘要
研究了约束程度对外掺MgO膨胀剂(MEA)混凝土变形及劈拉强度的影响,试模壁厚为5、7、10 mm,MEA活性指数为60、150 s,MEA掺量为0、6%和9%。试验结果表明:相同约束条件下MEA混凝土的应变随MEA膨胀剂掺量的增加而增大,养护温度越高,应变越大。30℃时,掺6%MEA-60的混凝土在壁厚为5 mm的试模约束下,28 d时的应变为11.8×10-6,大于在壁厚为10 mm的试模约束下混凝土的应变,但在壁厚为10 mm的试模约束下,其劈拉强度比在壁厚为5 mm试模约束下高13%。
Effect of restraint degree on the expansion and tensile splitting strength of concrete containing MgO-based expansive agent(MEA) were investigated.The wall thicknesses of the mold used to restrain the expansion of concrete specimen were 5,7,10 mm respectively.The activity values of MEA used were 60 s and 150 s,and the amount of MEA added in concrete were 0、6% and 9% respectively.Results showed that with increasing amount of MEA,the expansion of concrete increased correspondingly.Furthermore,higher curing temperature caused larger expansion strain of the concrete.The expansion strain of concrete containing 6% MEA-60 restrained by using 5mm-thick mold was 11.8×10-6 at 28 d when cured under 30 ℃,which was higher than that of the concrete restrained by using 10 mm-thick mold.and the tensile splitting strength of the latter,however,was increased by 13% in comparison to that of the former.
出处
《混凝土》
CAS
CSCD
北大核心
2012年第10期14-17,共4页
Concrete
基金
国家科技支持计划项目(2011BAE27B01)
国家重点基础研究发展计划(2009CB623105)
关键词
MEA膨胀剂
约束程度
应变
劈裂抗拉强度
MgO-based expansive agent
restraint degree
strain
tensile splitting strength
