摘要
为研究后浇普通混凝土(NC)与预制超高性能混凝土(UHPC)之间的黏结性能,以预制UHPC开槽密度和后浇NC强度等级为变量,完成了12组UHPC-NC黏结试件和4组新旧混凝土(强度等级C40)黏结试件的双面剪切试验。结果表明,设置有沟槽的预制UHPC与后浇NC间的机械咬合作用远大于后浇NC的抗剪强度,黏结试件的破坏模式为黏结面处的后浇NC被剪断。相同开槽密度下,UHPC-NC的黏结抗剪强度较新旧C40混凝土的黏结强度提高了19.63%~48.15%。后浇NC强度等级相同时,开槽密度越大,黏结抗剪强度越高,预制UHPC开槽密度为1.33、2.67、4对应的单槽抗剪强度分别为1.398、1.226、1.044 MPa;开槽密度和后浇NC强度等级均对UHPC-NC黏结面的抗剪强度有显著影响,开槽密度对UHPC-NC黏结抗剪强度的影响远大于后浇NC强度的影响。基于试验结果建立了考虑开槽密度和后浇NC强度影响的后浇NC与预制UHPC的黏结抗剪强度计算公式,计算结果与试验结果吻合良好。
In order to study the bond behavior between precast ultra-high performance concrete(UHPC)and post-cast normal concrete(NC),taking the slotting density and the strength of the post-cast normal concrete as variables,double-sided shear test of 12 groups of UHPC-NC composite specimens and four groups of new-old C40 composite specimens were conducted.The results show that the mechanical interaction of the bonding interface with precast UHPC slotting is much greater than the shear strength of the post-cast NC.Thus,the shear failure of the post-cast NC along the bonding interface is observed.Under the same slotting density,the bond shear strength of UHPC-NC is higher than that of new-old C40 concrete by 19.63%-48.15%.When the strength of the post-cast NC is the same,the greater the slotting density,the higher the shear strength at the bonding interfaces.When slotting densities of precast UHPC are 1.33,2.67,and 4,the shear strengths of single slotting are 1.398,1.226,and 1.044 MPa respectively.Slotting density and post-cast NC strength have significant effects on the shear strength of UHPC-NC bonding interface.The effect of slotting density on UHPC-NC bonding shear strength is much greater than that of post-cast NC strength.Based on the test results,a calculation formula for the bonding shear strength of precast UHPC and post-cast NC with consideration of the influence of slotting density and strength of post-cast NC was proposed,the calculated results were in good agreement with test tesults.
作者
王德弘
沈彤
鞠彦忠
郑文忠
曾聪
WANG Dehong;SHEN Tong;JU Yanzhong;ZHENG Wenzhong;ZENG Cong(School of Civil Engineering and Architecture,Northeast Electric Power University,Jilin 132012,China;Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education,Harbin Institute of Technology,Harbin 150090,China)
出处
《建筑结构学报》
EI
CAS
CSCD
北大核心
2020年第S02期411-419,共9页
Journal of Building Structures
基金
国家自然科学基金项目(51878128)
吉林省教育厅“十三五”科学技术研究规划项目(JJKH20190695KJ)
