摘要
为研究钢管超高性能混凝土短柱的偏压性能,以荷载偏心率和钢管径厚比为变化参数,设计了12个圆钢管UHPC短柱试件并对其进行偏心受压加载试验,分析了该类构件的破坏模式、荷载-挠度曲线、钢管应变和变形系数等,考察了主要因素对短柱偏压性能的影响规律。结果表明:试件的破坏特征为钢管屈服和核心混凝土压坏;荷载-挠度曲线有较明显的峰值点,偏心率越大和径厚比越小,曲线的下降段越平缓;达到60%峰值荷载时,钢管开始产生明显的约束作用,达到90%峰值荷载时,截面变形不再符合平截面假定;偏心率增大使试件的承载力和刚度下降,而径厚比减小可降低这种不利影响。在试验基础上,结合数值模拟对短柱的N-M曲线进行分析,建立了临界偏心率和套箍系数的关系表达式,并基于此提出短柱偏压承载力实用计算方法,理论与试验结果吻合较好。
To study the eccentric compression performance of ultra-high performance concrete filled with steel tubular short columns,12 circular specimens were designed and tested under eccentric compression by taking the load eccentricity and diameter-thickness ratio as variation parameters.The failure mode,load-deflection curves,strain of steel tubes,and deformation coefficient of these members were analyzed.The effects of main factors on the eccentric compression performance of short columns were explored.The results show that the failure of specimens is characterized by the yielding of the steel tube,followed by the crushing of the core concrete.The load-deflection curves have clear peak points,and the greater the eccentricity and the smaller the diameter-to-thickness ratio,the smoother the drop section of the load-deflection curves.At 60%of the peak load,the steel tube begins to produce obvious confinement;at 90%of the peak load,the section deformation no longer meets the plane section assumption.As the eccentricity increases,the load-bearing capacity and stiffness of the specimens decrease,and the decrease in the diameter-to-thickness ratio can reduce this adverse effect.Based on the experiment,the N-M curve of the short column is analyzed by numerical simulation and an expression for the relationship between the critical eccentricity and the confining coefficient is established.The practical calculation method of short column bearing capacity is proposed,and the theoretical and experimental results are in good agreement.
作者
王秋维
梁林
王程伟
苏宁粉
WANG Qiuwei;LIANG Lin;WANG Chengwei;SU Ningfen(School of Civil Engineering,Xi'an University of Architecture and Technology,710055 Xi'an,China;State Key Laboratory of Green Building in Western China,Xi'an University of Architecture and Technology,710055 Xi'an,China;Key Lab of Structural Engineering and Earthquake Resistance,Ministry of Education(XAUAT),710055 Xi'an,China)
出处
《应用力学学报》
CAS
CSCD
北大核心
2024年第3期536-545,共10页
Chinese Journal of Applied Mechanics
基金
国家自然科学基金资助项目(No.51878543)
陕西省教育厅科学研究计划项目(No.17JS063)。
关键词
钢管超高性能混凝土
偏压短柱
数值分析
N-M关系
承载力计算
ultra-high performance concrete filled with steel tubular(UHPCFST)
eccentric compression short column
finite element(FE)analysis
N-M relationship
calculation of bearing capacity
