摘要
为探究CEA和HME-V外加剂在变温历程实体混凝土结构中抗裂的效果,研究了温度历程对此类混凝土抗裂效能的影响。结果表明:温度历程对CEA和HME-V外加剂补偿收缩变形的影响显著,CEA的膨胀速率随温度的升高而加快,且在开裂风险高的温降阶段无补偿收缩变形作用,HME-V在温升及温降阶段均发挥较好的补偿变形作用,且与混凝土温度历程匹配较好;实际工程宜评估实体结构变温历程条件下CEA和HME-V外加剂的补偿收缩变形能力来优选抗裂效能较好的外加剂,并在满足设计要求的情况下,参考变温历程条件下混凝土强度的发展来确定拆模时间。
In order to study the CEA and HME-V admixture in entity structure under variable temperature condition,the efficacy of concrete with CEA and HME-V under variable temperature condition was investigated.The results indicate that temperature condition has a significant impact on the compensation shrinkage deformation of crack-resistance agent.The expansion rate of CEA increases with the increase of temperature,and no compensation shrinkage deformation is generated in temperature drop stage with high cracking risk.HME-V can compensate shrinkage deformation not only in the temperature rise stage but also in the entire process,which matches well with the temperature process of entity structure.The ability of CEA and HME-V admixture to compensate shrinkage deformation should be evaluated to select the admixture with better crack resistance and form removal time for engineering in accordance with design and standards.
作者
卞桂荣
李宝枝
李明
徐文
田倩
BIAN Gui-rong;LI Bao-zhi;LI Ming;XU Wen;TIAN Qian(No.3 Engineering Co.,Ltd.of CCCC Third Harbor Engineering Co.,Ltd.,Nanjing 210011,China;State Key Laboratory of High Performance Civil Engineering Materials,Jiangsu Research Institute of Building Science Co.,Ltd.,Nanjing 210008,China;Jiangsu Sobute New Materials Co.,Ltd.,Nanjing 211103,China;College of Materials Science and Engineering,Southeast University,Nanjing 211189,China)
出处
《混凝土与水泥制品》
2021年第2期23-26,共4页
China Concrete and Cement Products
基金
国家重点研发计划项目(2017YFB0310100)
中铁隧道集团科技创新计划项目(隧研合2017-03)
江苏省交通工程建设局科技项目。
关键词
变温历程
膨胀速率
全过程补偿
裂缝控制
Variable temperature condition
Expansion rate
Compensating shrinkage in entire process
Cracking control
