摘要
文中基于致密堆积理论进行钢管外包自密实混凝土配制,并研究了CEA膨胀剂对自密实混凝土收缩补偿特性与开裂敏感性的影响.结果表明:致密堆积理论配制的钢管外包自密实混凝土工作性能良好、28 d抗压强度39.2 MPa,满足工程应用要求.CEA膨胀剂在自密实混凝土成型5 h后开始作用,14 d左右达到平衡,补偿收缩效果显著.当CEA膨胀剂的掺量为10%时,早期抗裂性优异,抗裂等级为Ⅰ级.当超过10%后,抗裂性能提升并不明显,而且还有过度膨胀造成自密实混凝土内部结构破坏,降低抗压强度的风险.
Based on the dense packing theory,the self-compacting concrete wrapped with steel tube was prepared,and the influence of CEA expansive agent on shrinkage compensation characteristics and cracking sensitivity of self-compacting concrete was studied.The results show that the self-compacting concrete coated with steel tube prepared by dense packing theory has good working performance,and the 28-day compressive strength is 39.2 MPa,which meets the requirements of engineering application.CEA expansive agent begins to act after 5 h of self-compacting concrete molding,and reaches a balance in about 14 d,and the shrinkage compensation effect is remarkable.When the content of CEA expansive agent is 10%,the early crack resistance is excellent,and the crack resistance grade is grade I.When it exceeds 10%,the improvement of crack resistance is not obvious,and there is a risk that excessive expansion will damage the internal structure of self-compacting concrete and reduce its compressive strength.
作者
袁文
李宝清
王开凤
李存
朱云升
YUAN Wen;LI Baoqing;WANG Kaifeng;LI Cun;ZHU Yunsheng(Sichuan Transportation Construction Group Co.Ltd.,Chengdu 610047,China;School of Transportation and Logistics Engineering,Wuhan University of Technology,Wuhan 430063,China)
出处
《武汉理工大学学报(交通科学与工程版)》
2025年第1期167-173,共7页
Journal of Wuhan University of Technology(Transportation Science & Engineering)
关键词
钢管外包自密实混凝土
致密堆积理论
CEA膨胀剂
收缩补偿性能
抗裂性
steel pipe with self-compacting concrete
dense packing theory
CEA expansion agent
shrinkage compensation property
crack resistance