多腔钢管混凝土分叉柱力学性能有限元分析

为研究异形截面多腔钢管混凝土分叉柱的力学性能及设计方法,以北京某超高层建筑异形截面多腔钢管混凝土巨型分叉柱为原型,在已进行的低周反复荷载试验基础上,对异形截面多腔钢管混凝土分叉柱抗震性能进行有限元分析,研究了不同构造措施、不同钢材及混凝土强度等级等参数对钢管混凝土分叉柱抗震性能的影响.结果表明:基于本文提出的有限元建模方法,所得有限元分析结果与试验结果吻合较好;适当增加腔体数,设置肋板、角钢和钢管能够有效提高异形截面钢管混凝土分叉柱抗震性能;在等用钢量下,增加腔体数量比增加钢板厚度能更有效地提高分叉柱抗震性能;不同材料强度对异形截面钢管混凝土分叉柱抗震性能有较大影响,在进行其抗震设计时,宜选用强度等级匹配的钢材与混凝土.

FEM analysis on multi-cell CFST bifurcated columns

To study the mechanical properties and design method of CFST columns with special-shaped cross-section, based on the special-shaped multi-cell CFST bifurcated columns of a super-high building under construction in Beijing, the FEM analysis on the seismic behavior of the special-shaped concrete-filled bifurcated steel tube columns was carried out. The test parameters were the different constructional measures, different steel and concrete grades. The results show that the developed FEM analysis method has adequate accuracy compared with the test results. The seismic behavior of the columns increased with increasing the number of the cells, the installation of the stiffener, L-type steel and steel tube. Increasing the number of the cavities has a better effect on seismic behavior than the increasing thickness of the steel tube in the case of the same steel consumption. The materials strength has a great influence on the seismic performance of the bifurcated column, and the strength matching between the steel and concrete should be considered in seismic design.