多腔钢管钢筋混凝土短柱轴压承载力实用计算方法

A practical method for calculating axial bearing capacity of multi-cell RCFST short column

多腔钢管钢筋混凝土柱具有承载力大、抗震延性好、易于施工等优点,为巨型结构提供了一种有效的解决方案,并在高银117等超高层项目中得到了应用,但是尚缺乏相应的承载力理论计算公式。首先基于Richart强度公式,对正方形2等分4腔体钢管钢筋混凝土短柱进行轴压承载力的理论推导,得到了相应的承载力公式,然后推广到正方形多等分的多腔钢管钢筋混凝土巨柱;给出了基于过-张-翁强度公式的正方形等分多腔体钢管钢筋混凝土短柱轴压承载力公式和低箍筋约束效应下的多腔钢管钢筋混凝土短柱承载力公式;结合承载力公式对腔体的设置进行了分析,对于大截面巨柱,多腔钢管钢筋混凝土巨柱较单腔钢管钢筋混凝土柱有效提高了承载力,多腔钢管钢筋混凝土巨柱腔体不宜过多。

The multi-cell RCFST( Reinforced Concrete Filled Steel Tube) column has the advantages of bearing capacity,seismic ductility and construction. It provides an effective solution for the mega frame structure and has been applied in the projects of Tianjin Gaoyin 117,etc,yet the bearing capacity formula of the multi-cell RCFST short column is lack. Based on the Richart strength criterion,the formula of the bearing capacity of the multi-cell RCFST short column with 4 equal parts is deduced. The bearing capacity formula is obtained and then extended to the other multi-cell RCFST column with several equal parts. Based on the Guo-Zhang-Weng strength criterion. The formula of bearing capacity of the multi-cell RCFST short column with several equal parts is given and the formula is suggested for the other multi-cell RCFST short column. According to the formula of bearing capacity,the multi-cell RCFST column is more effective than the single-cell RCFST column.