摘要
在钢管内部分填充混凝土形成的部分填充钢管混凝土柱能提升钢管柱的强度、刚度和抗震性能,适用于桥墩柱和框架中下部柱子。基于验证的精细化有限元分析模型,对部分填充方钢管混凝土柱在轴压和水平荷载共同作用下的受力性能进行了参数分析,主要分析了轴压比(0.1~0.6)、钢管宽厚比(20~50)、钢材强度(Q235~Q690)、混凝土强度(C20~C60)、截面宽度(200~600 mm)和柱子高宽比(4~16)的影响。结果表明:填充率会影响部分填充钢管混凝土柱的破坏模式,随填充率增大,柱子破坏模式从钢管截面破坏转变为柱底部钢管混凝土截面破坏,柱子的强度和刚度提高;混凝土填充率增加到一定程度后柱底钢管混凝土截面形成塑性铰,此时达到最优填充率,继续增加填充率,柱子的强度及延性基本不变;轴压比、宽厚比、钢材强度、混凝土强度、截面宽度和高宽比对最优填充率的影响呈现出规律性变化;建立了部分填充方钢管混凝土柱在轴力和水平力作用下的简化力学模型并提出了其最优填充率的计算方法。
A partially concrete-filled steel tubular(CFST) column, by partially filling the steel tube with concrete, can improve the strength, stiffness and seismic performance of the steel tubular column. It is suitable for bridge piers and lower-story columns in a framing system. Based on a validated and refined finite element analysis model, this paper analyzed the mechanical performance of partially CFST columns under combined axial compression and horizontal loads. The primary analysis parameters included the axial compression ratio(0.1-0.6), steel tube width-to-thickness ratio(20-50), steel strength(Q235-Q690), concrete strength(C20-C60), section width(200-600 mm), and aspect ratio(4-16). The results showed that the filling ratio affected the failure mode of partially CFST columns. As the filling ratio increased, the failure mode changed from steel tube section failure to CFST section failure, thereby improving the strength and stiffness of the column. After the filling ratio increased to a certain level, a plastic hinge formed at the bottom of the column, and the strength and ductility of the column no longer increased. At this time, the concrete had achieved the optimal filling ratio. The influence of the axial compression ratio, width-to-thickness ratio, steel strength, concrete strength, section width and aspect ratio on the optimal filling ratio showed regular changes. A simplified model of partially CFST columns subjected to combined axial compression and the lateral load was established, and the calculation method for its optimal filling ratio was proposed.
作者
张兴疆
甘丹
何明胜
ZHANG Xingjiang;GAN Dan;HE Mingsheng(College of Water&Architectural Engineering,Shihezi University,Shihezi 832003,China;School of Civil Engineering,Chongqing University,Chongqing 400045,China)
出处
《建筑钢结构进展》
CSCD
北大核心
2023年第2期32-41,共10页
Progress in Steel Building Structures
基金
国家自然科学基金(51878097)。
关键词
部分填充方钢管混凝土柱
最优填充率
有限元分析
水平荷载
参数分析
破坏模式
partially concrete-filled square steel tubular column
optimal filling ratio
finite element analysis
horizontal load
parameter analysis
failure mode
