开孔钢板加劲中空夹层圆钢管混凝土柱轴压性能

Research on Mechanical Properties of Concrete-Filled Double-Skin Circular Steel Tubular Columns Stiffened by Perforated Steel Plates Under Axial Compression

对开孔钢板加劲中空夹层圆钢管混凝土柱的轴压性能进行了研究。采用ABAQUS软件建立有限元模型,在验证模型可靠性的基础上,对构件进行荷载-位移曲线分析、应力分布与破坏模式分析和参数分析,进而提出开孔钢板加劲中空夹层圆钢管混凝土柱轴压承载力的设计方法。研究结果表明:开孔钢板可以增强钢管和混凝土的共同受力和约束效应。构件各参数推荐取值:钢材牌号Q355、混凝土强度等级C60、开孔直径35 mm、开孔间距15 mm、加劲钢板厚度5 mm、加劲钢板个数4个,此时,与中空夹层钢管混凝土柱比较,承载力可提高9.6%,与不开孔钢板加劲中空夹层钢管混凝土柱的承载力比较,承载力只降低1.9%,因此开孔可以节省钢材,且保证一定的承载力。通过将规范中的计算公式,增加加劲钢板承载力贡献项,同时考虑开孔直径对承载力的影响和钢板对混凝土强度提高的作用,提出的轴压承载力设计方法可以较为安全地预测其轴压承载力。

The mechanical properties of concrete-filled double-skin steel tubular columns stiffened with per-forated steel plates was studied.The finite element model was established by ABAQUS software.On the ba-sis of verifying the reliability of the model,the load-displacement curve,stress distribution,failure mode and parameter analysis of the members were carried out.Furthermore,the design method of bearing capaci-ty of concrete-filled double-skin steel tubular columns stiffened by perforated steel plates under axial com-pression was proposed.The results showed that the perforated steel plate could enhance the joint force and restraint effect of steel tube and concrete.The recommended values of each parameter of the component should be:steel grade Q355,concrete strength grade C60,opening diameter 35 mm,opening spacing 15 mm,stiffened steel plate thickness 5 mm,and the number of stiffened steel plates should be 4,at this time,the bearing capacity could be increased by 9.6%compared with the concrete-filled double-skin steel tube column,and the bearing capacity is only reduced by 1.9%compared with the bearing capacity of the concrete-filled double-skin steel tube column stiffened with steel plates.Therefore,the opening could save steel and ensure a certain bearing capacity.By adding the contribution of the bearing capacity of the stiffened steel plate to the calculation formula in the specification,and considering the influence of the opening diame-ter on the bearing capacity and the effect of the steel plate on the improvement of the concrete strength,the proposed design method of axial bearing capacity could safely predict its axial bearing capacity.