建筑结构学报2024，Vol.45Issue(9)：100-112,13.DOI:10.14006/j.jzjgxb.2023.0709
钢筋在超高性能混凝土中的锚固与搭接性能试验研究
Test study on anchorage and lap splicing performance of rebars in UHPC
摘要
Abstract
To study the bonding performance between ultra-high performance concrete(UHPC)and rebars,45 direct pull-out specimens and 39 lap-splicing specimens containing new and old UHPC interfaces were designed.The effects of rebar diameter,UHPC cover thickness,anchorage and lap splicing length,loading form,stirrup configuration and interface treatment on the bonding performance were studied through pull-out tests and lap-splicing tests.The results show that for anchorage specimens,the failure mode and bonding strength are mainly influenced by the cover thickness and anchorage length.When cover thickness is less than 3d(d represents the diameter of rebar),all specimens exhibit UHPC splitting failure,and the bonding strengths are relatively small.When cover thickness reaches 3d or above,specimens with the anchorage length of 5d show pull-out failure after rebar yielding,resulting in a higher bond strength.When the anchorage length reaches 10d or more,all specimens fail in the fracture of rebar,and the average decrease of bonding strength is more than 50％.For lap-splicing tests,specimens without stirrups all exhibit interface splitting failure.For specimens with volumetric stirrup ratio no less than 0.2％,bonding performance is mainly influenced by lap splicing length.When the lap splicing length is longer than 6d,the failure mode changes from pull-out failure to fracture of rebar,and the bond strength significantly decreases.Based on the test results,it is recommended that the UHPC cover thickness should be within the range of 3d-5d for pull-out specimens.Besides,design formula of the minimum anchorage/lap splicing length is proposed and recommended values of the critical bonding length coefficient are given.关键词
超高性能混凝土/钢筋/锚固/搭接长度/黏结性能/黏结强度Key words
ultra-high performance concrete/rebar/anchorage and lap splicing length/bonding performance/bonding strength分类
土木建筑引用本文复制引用
郭保第,丁然,李玥一,聂鑫,许见超..钢筋在超高性能混凝土中的锚固与搭接性能试验研究[J].建筑结构学报,2024,45(9):100-112,13.基金项目
中国铁道科学研究院集团有限公司基金资助项目(2021YJ146),国家自然科学基金项目(52325802,52121005). （2021YJ146）
