摘要
为探究玄武岩纤维筋(BFRP筋)与再生骨料混凝土的粘结性能,对其进行中心拔出试验。基于试验结果,探究了其破坏形态以及粘结机理,研究再生混凝土强度等级、筋材直径和再生骨料替代率对BFRP筋和再生骨料混凝土粘结性能影响。结果表明,BFRP筋与再生骨料混凝土粘结有拔出破坏和劈裂破坏两种破坏形态;BFRP筋与再生骨料混凝土粘结滑移曲线可分为微滑移段、滑移段、下降段和残余应力段;提高再生混凝土的强度等级可以延缓混凝土内部裂缝的产生与演化,进一步提高BFRP筋表面肋与混凝土之间的机械咬合作用,增大BFRP筋与再生混凝土的粘结强度;因剪力滞后效应,BFRP筋与再生骨料混凝土的粘结强度随着BFRP筋直径的增加而降低;再生骨料替代率的增加会对BFRP筋和再生骨料混凝土的粘结应力产生不利影响。
In order to explore the bond properties of basalt fiber reinforced bar(BFRP bar)and recycled aggregate concrete,the central pull-out test was carried out.Based on the test results,the failure mode and bond mechanism were explored,and the effects of recycled concrete strength grade,bar diameter and recycled aggregate replacement rate on the bond properties between BFRP bars and recycled aggregate concrete were studied.The results show that there are two failure modes of pull-out failure and splitting failure between BFRP bars and recycled aggregate concrete.The bond-slip curve of BFRP bar and recycled aggregate concrete can be divided micro-slip stage,slip stage,descending stage and residual stress stage.Increasing the strength grade of recycled concrete can delay the generation and evolution of internal cracks in concrete,further improve the mechanical interlocking between the surface ribs of BFRP bars and concrete,and increase the bond strength between BFRP bars and recycled concrete.Due to the shear lag effect,the bond strength between BFRP bars and recycled aggregate concrete decreases with the increase of the diameter of BFRP bars.The increase of recycled aggregate replacement rate will adversely affect the bond stress between BFRP bars and recycled aggregate concrete.
作者
张振雷
刘华新
徐佳宁
ZHANG Zhenlei;LIU Huaxin;XU Jianing(College of Railway Engineering,Liaoning Railway Vocational and Technical College,Jinzhou 121001,China;College of Civil and Architectural Engineering,Liaoning University of Technology,Jinzhou 121001,China)
出处
《建筑结构》
北大核心
2024年第10期100-105,共6页
Building Structure
基金
辽宁省教育厅科学基金项目(LTKY2019111)。
