摘要
为研究带拉杆约束矩形截面钢管混凝土短柱的抗震性能，以轴压比、约束拉杆间距和截面长宽比为主要参数，进行了4个无拉杆约束和11个带拉杆约束矩形钢管混凝土短柱试件的低周往复加载试验。研究了其破坏过程、滞回性能、承载能力、变形能力、刚度退化及耗能能力等，并基于数值分析给出了带约束拉杆矩形截面钢管混凝土短柱压弯承载力计算式。结果表明：钢管板件宽厚比为50和67、剪跨比为3的矩形截面钢管混凝土短柱的滞回曲线饱满，没有明显的捏缩；设置约束拉杆提高了试件的承载能力、变形能力及耗能能力；带约束拉杆试件的极限位移角在1／19-1／50之间，位移延性系数在3．28-6．25之间；破坏时的等效黏滞阻尼系数在0．3以上；增加轴压比降低了试件的延性；减小约束拉杆间距可明显改善柱的抗震性能；保持截面宽度不变，增加截面长宽比，可提高试件承载力，但延性降低。提出的带约束拉杆矩形截面钢管混凝土短柱的压弯承载简化计算式的计算结果与试验结果吻合较好。
To study the seismic behavior of rectangular concrete-filled steel tubular （CFT） stub columns with binding bars, an experiment of four specimens of rectangular CFT stub columns without binding bars and eleven specimens with binding bars was designed and carried out under cyclic lateral load with different axial load ratios, spacing of binding bars and depth-width ratios. The failure patterns, hysteretic properties, bearing capacities, rigidity degeneration, deformation ability, energy dissipation capacity of the specimens were investigated. Additionally, based on the numerical analysis, the simplified formula for axial force-moment capacity of the columns was developed. The results indicate that the rectangular CFT stub columns, with width-thickness ratios of 50 and 67, and shear-span ratio of 3, have plump hysteretie curves. The bearing capacity, deformation ability and energy dissipation of the specimens with binding bars are remarkably improved. The ultimate drift ratio is between 1/19 and 1/50 and the displacement ductility coefficient is about 3. 28-6. 25 for the specimens with binding bars. The equivalent viscous damping coefficient is above 0.3 for all specimens. The ductility decreases with the increase of axial load ratio. With the decreasing of the binding bars keeping the width of section unchanged, the seismic behavior of the specimens is obviously improved. With the increase of the depth-width ratio, the bearing capacity increases, while the ductility decreases. The calculation results of axial-force moment capacity by the simplified formula have good agreement with the experimental ones.
出处
《建筑结构学报》
EI
CAS
CSCD
北大核心
2016年第2期133-141,共9页
Journal of Building Structures
基金
广州市珠江科技新星专项(2012J2200100)
中央高校基本科研业务费专项资金(2014ZZ0026)
