摘要
超高性能混凝土(UHPC)具有优良的力学性能和耐久性能,为了推广UHPC在桥梁工程中的应用,对新浇UHPC与普通混凝土(NC)界面黏结性能进行了研究。通过劈裂试验、抗折试验和双面剪切试验,分别研究了经不同界面处理(凿毛/表干润湿/膨胀剂)的UHPC-NC在拉伸状态和剪切状态下的界面黏结强度,通过添加膨胀剂对新浇UHPC的收缩性能进行调控,研究了收缩对界面黏结性能的影响。结果表明:人工凿毛、表干润湿和添加膨胀剂处理能显著提高新浇UHPC和NC的界面黏结强度;当UHPC-NC为表干润湿处理的凿毛界面,膨胀剂最佳掺量为10%时,新浇UHPC收缩得到了最大的补偿,此时新旧混凝土界面黏结强度更高。
Ultra high performance concrete(UHPC)has excellent mechanical and durability properties.In order to promote the application of UHPC in bridge engineering,the interfacial bonding performance between newly poured UHPC and ordinary concrete(NC)was studied.The interfacial bonding strength of UHPC-NC under different interface treatments(chiseling/surface wetting/expansion agent)in tensile and shear states was studied through splitting test,flexural test and double-sided shear test.The shrinkage performance of newly poured UHPC was controlled by adding expansion agent,and the effect of shrinkage on interfacial bonding performance was studied.The results show that manual chiseling,surface drying and wetting,and the addition of expansion agents can significantly improve the interfacial bonding strength of newly poured UHPC and NC.When UHPC-NC is a chiseled interface treated with surface drying and wetting,the optimal dosage of expansion agent is 10%,and the shrinkage of newly poured UHPC is maximally compensated.At this time,the bonding strength between the new and old concrete interfaces is higher.
作者
赵兴华
许祥贵
梁广振
韩笑
ZHAO Xinghua;XU Xianggui;LIANG Guangzhen;HAN Xiao(The Fourth Engineering Co.,Ltd.,of CCCC First Highway Engineering Co.,Ltd.,Nanning 530031,China;CCCC Highway Bridge National Engineering Research Centre Co.,Ltd.,Beijing 100120,China)
出处
《混凝土》
CAS
北大核心
2024年第6期206-209,214,共5页
Concrete
基金
中国交通建设集团有限公司科技研发项目(KJYF-2022-A-01J)
中交一公局集团有限公司科技研发项目(2020-A-11)。
