论文部分内容阅读
为提高钢筋混凝土(RC)柱的轴压性能,在截面中部设置核心钢管并填充高强混凝土,形成核心钢管混凝土(CSTRC)叠合柱。完成了7个CSTRC短柱和2个RC短柱的单向轴压试验,主要变化参数为核心钢管配钢率和钢管内填混凝土强度。研究表明:设置核心钢管后,试件承载能力和变形性能得到显著改善;CSTRC柱的轴压承载力随钢管配钢率和钢管内填混凝土强度的增大而增大,轴向变形能力随钢管内填混凝土强度的增大而减小。建立了CSTRC柱的有限元模型,在试验验证的基础上,对核心钢管与内外混凝土的相互作用规律进行了研究。结果表明,试件达到极限荷载时,钢管外部混凝土对钢管的约束作用可以忽略,而钢管对内填混凝土有明显约束作用。基于试验和有限元分析的结果,提出了CSTRC柱轴压承载力计算式。
In order to improve the axial compression performance of reinforced concrete (RC) columns, a core steel tube is installed in the middle of the section and filled with high-strength concrete to form a core CSTC composite column. The uniaxial axial compression tests of seven CSTRC stubs and two RC stubs were completed. The main parameters for the change were the steel ratio of core steel pipe and the concrete filled with steel pipe. The results show that the bearing capacity and the deformation capacity of the specimens are significantly improved after the core steel tube is set up. The axial compressive load of CSTRC columns increases with the steel ratio and the strength of the steel filled concrete. Filling concrete strength increases and decreases. The finite element model of CSTRC column was established. Based on the experimental verification, the interaction between the core steel pipe and the internal and external concrete was studied. The results show that when the specimen reaches the ultimate load, the confinement effect of the external steel pipe on the steel pipe can be neglected, while the steel pipe has obvious restraint on the internal concrete filling. Based on the results of tests and finite element analysis, the calculation formula of axial bearing capacity of CSTRC column is proposed.