CFRP约束竹条-薄壁圆钢管组合柱轴压性能研究  

Study on axial compressive behavior of CFRP-constrained bamboo strips-circular thin-walled steel tube composite columns

作　　者：田黎敏[1] 李宸 廖述荟 寇跃峰 郝际平[1] TIAN Limin;LI Chen;LIAO Shuhui;KOU Yuefeng;HAO Jiping(School of Civil Engineering,Xi’an University of Architecture and Technology,Xi’an 710055,China)

机构地区：[1]西安建筑科技大学土木工程学院,陕西西安710055

出　　处：《建筑结构学报》2022年第12期243-254,共12页Journal of Building Structures

基　　金：科技部国家重点研发计划(2017YFC0703502);青海省高原绿色建筑与生态社区重点实验室开放基金计划项目(KLKF-2020-001)。

摘　　要：为延缓胶黏剂的失效,防止薄壁钢管过早发生屈曲,同时应对竹材防火、防虫、防腐性能差的缺点,提出一种CFRP约束竹条-薄壁圆钢管组合柱。制作9个短柱和4个长柱并对其进行轴心受压试验,继而基于验证后的有限元模型,分析竹条厚度、CFRP层数、钢管截面以及长细比对轴压性能的影响规律,在此基础上提出组合柱轴压承载力理论计算公式。研究结果表明:组合柱的破坏模式为柱中材料破坏、端部压溃破坏及整体失稳;组合柱的承载力随着竹条厚度和钢管直径的增加而增大,随着长细比的增大而减小;CFRP在中小长细比(λ_(c)≤50)组合柱中的环箍作用显著,但在大长细比(λ_(c)>50)组合柱中作用有限;组合柱发生整体失稳破坏的长细比界限值为19;各参数对组合柱承载力提升效率的影响不同。试验、有限元模拟及理论分析的结果吻合较好,承载力公式的计算结果与试验或有限元分析结果的平均误差均低于5.0%,最大误差均低于10%,说明轴心受压承载力计算公式具有较高的精度,适用于预测CFRP约束竹条-薄壁圆钢管组合柱的承载力。To delay the failure of the adhesive,prevent premature buckling of thin-walled steel pipes,and to address the weaknesses of bamboo in fire prevention,insect prevention,and corrosion resistance,a novel type of composite columns,namely,CFRP-constrained bamboo strips-circular thin-walled steel tube columns was proposed.A series of axial compression tests were conducted on the composite columns(including nine short columns and four long columns)and the results were used to verify the finite element(FE)model.The verified FE model was then used to investigate the effects of thickness of bamboo strips,number of CFRP layers,steel pipe section and slenderness ratio on the axial compressive behavior of the columns.On this basis,the theoretical equations of the axial compressive capacity of the composite columns were proposed.The results show that there are three failure modes of the composite columns:the material damage in the middle of the columns,crushing failure at the end of the columns,and global instability failure.The bearing capacity of the composite columns increases with the thickness of the bamboo strips and the diameter of the steel pipes,and decreases with the slenderness ratio.CFRP has a significant confinement effect in the composite columns with small and medium slenderness ratios(λ_(c)≤50),but has a limited effect in the composite columns with large slenderness ratios(λ_(c)>50).When the slenderness ratio is less than 19,the composite columns would undergo material failure,otherwise the composite columns would fail by instability.The effects of various parameters on the improvement efficiency of the bearing capacity are different.The results of the test,finite element simulation,and theoretical analysis are in good agreement.The average error between the results by the theoretical equations and the experimental or finite element results is less than 5.0%,and the maximum error is less than 10%,indicating that the established calculation methods have high accuracy and are suitable for predicting the beari

关 键 词：组合柱 CFRP 薄壁圆钢管 竹条 轴心受压试验 承载力 

分 类 号：TU398.903[建筑科学—结构工程] TU311.41