异形截面多腔钢管混凝土巨型分叉柱轴压性能试验研究

Compressive behavior of specially-shaped multi-cell mega-bifurcated concrete filled steel tubular columns

为研究北京"中国尊"多腔钢管混凝土巨型分叉柱不同构造措施对其受压性能的影响,进行了2个1/10缩尺的分叉柱节点区域模型试件轴心受压力学性能试验。设计了原型柱缩尺试件BAC以及在试件BAC基础上未配置纵向加劲肋及构造钢筋的试件WAC。分析了试件破坏特征,承载力、刚度及退化过程、延性、耗能能力等。研究表明:试件BAC满足受力要求,承载力较高、刚度退化速率缓慢、延性较好、耗能能力较强;与试件BAC相比,试件WAC构造措施简化,但其承载力变化不大,刚度退化较快、延性较差、耗能能力较弱;异形截面钢管混凝土柱后期变形发展与构件截面不规则程度有关。在忽略横隔板作用情况下,采用不同承载力计算方法并按是否考虑竖向构造措施的影响进行了承载力计算,结果表明采用不同方法计算承载力时,横隔板对承载力的贡献均较大,且因计算方法不同存在差异。

To investigate the influences for multi-cell mega-bifurcated concrete filled steel tubular columns（ CFST）with different construction measures in the Chinese Zun project in Beijing,tests on two 1 ∶ 10 scaled specimens of multi-cell mega-bifurcated CFST were conducted. The specimen BAC had longitudinal stiffeners and constructional reinforcements,which were not provided for the specimen WAC. The failure modes and static properties were investigated. The test results demonstrate that the specimen BAC conforms to the mechanical requirements and behave advantages over the specimen WAC in terms of the bearing capacity,stiffness degeneration,ductility and energy dissipation capacity. The analysis results reveal that the late deformation of multi-cell mega-bifurcated CFST is related to the shape of cross section. In case of requiring no diaphragms,the bearing capacity with or without longitudinal constructions was calculated by different methods. However,the calculated results indicate that the contributions of diaphragms to the bearing capacity are remarkable and different because of the methods of calculation.