以16根试件的低周反复荷载试验为基础,对SRC-RC竖向混合结构中的转换柱进行了截面配钢分析。结果表明:型钢的配钢率对转换柱抗震性能与基本力学行为存在较大影响,配钢率较大试件的位移延性系数较小,而承载力相对较大;配钢率越大,型钢分配到的剪力越大,转换柱的内力畸变越严重,变形能力越差;随着配钢率的增大,混凝土的损伤加快,转换柱的强度衰减更显著;型钢增强了截面的抗弯刚度,提升了试件的弹性侧移刚度,但对试件加载中后期的侧移刚度影响较小。通过理论分析与试验研究相结合的方式,确定了转换柱合理型钢截面的最大抗弯承载力,避免转换柱发生严重的剪切破坏,保证其具有可应用于工程建设的力学性能。试验数据与分析结果可为SRC-RC竖向混合结构的抗震设计与工程建设提供参考。
The cross section arrangement of shape steel in transfer columns of SRC-RC hybrid structure was analyzed based on low cyclic reversed loading test of 16 specimens. The results showed that area ratio of shape steel has serious effect on seismic behavior of transfer columns. Displacement ductility decreases along with the increment of shape steel arrangement, hut carry capacity increases at the same time. Partially existed shape steel makes the aberrance of internal stress and hence leads serious shear effect to transfer columns, so deformation ability and postpeak behavior degenerate when area ratio of shape steel promotes. Shape steel not only makes the flexural stiffness of cross section advanced but also postpones the appearance of cracks, and hence increases elastic lateral stiffness of specimens, but lateral stiffness at yielding point has httle effect by shape steel arrangement. Through test and theoretical calculation, maximum of bending capacity in rational range of shape steel arrangement was confirmed which can be used to prohibit serious shear effect and insure deformation ability against brittle failure. Test data and the analysis results could provide references to seismic design and construction of hybrid structure.