钢骨混凝土异形截面柱抗震性能试验及分析

Test and analysis of the seismic performance of SRC columns of irregular sections

北京财富中心一期工程办公楼框筒结构的外框柱为钢骨混凝土柱,它采用了两种柱截面类型,一种为截面形如乒乓球拍的钢骨混凝土异形截面柱,一种为钢骨混凝土圆形截面柱。为了研究这种钢骨混凝土异形截面柱的抗震性能并与钢骨混凝土圆形截面柱作比较,从实际工程中选择了具有代表性的3根钢骨混凝土异形截面柱和1根钢骨混凝土圆形截面柱,进行了低周反复荷载下的模型试验,模型按1/4缩尺。重点探讨了各钢骨混凝土柱的承载力、刚度及其衰减过程、延性、滞回特性及破坏特征。用基于平截面假定的条带法建立了这种钢骨混凝土异形截面柱正截面承载力的计算方法,圆形截面则作为其分析的特例,计算分析了轴压比及含钢骨率对正截面承载力的影响,其正截面承载力计算结果与实测值符合较好。试验及分析表明,钢骨混凝土异形截面柱抗震性能良好,经合理设计可以满足抗震设计的要求。

SRC columns of irregularly-shaped sections, something like table tennis racket, are employed in the Beijing Fortune Plaza. Previous research on this type of SRC column has not been known. In order to understand the seismic behavior of this type of SRC column, three irregularly-shaped and one circular SRC columns of 1/4 scale were designed and tested with low cyclic loading. The load-carrying capacity, stiffness and its attenuation, ductility, hysteretic property and failure mechanism of the irregularly shaped columns were studied and compared with those of the column of a circular section. The load-carrying capacity of the test specimens was calculated with the strip method, and the calculation results agree well with the experimental results. The test and study indicate that this type of SRC column has good seismic behavior and meets the demand if rationally designed.