巨型钢管混凝土柱分配梁构造下竖向荷载传递机理研究(Ⅱ):数值分析  

Compression load transfer mechanism of distributive beam detailings in large-section CFT columns(Ⅱ) : numerical simulation

作　　者：张元植[1] 罗金辉[1] 李元齐[1] 傅学怡[1,2] 沈祖炎[1] 

机构地区：[1]同济大学,上海200092 [2]悉地国际深圳设计顾问有限公司,深圳518048

出　　处：《土木工程学报》2016年第12期16-26,共11页China Civil Engineering Journal

基　　金：国家自然科学基金(51208375)

摘　　要：为研究超高层建筑结构中大型转换梁(或转换桁架)与巨型钢管混凝土柱连接处采用分配梁构造时的钢-混凝土共同工作性能,文中结合试验结果进行精细化数值分析。首先,采用ABAQUS软件建立设置分配梁构造的巨型钢管混凝土柱精细化数值模型,得到的轴压荷载-位移曲线、混凝土工作承担系数曲线和破坏模态均与试验结果吻合良好,验证有限元模型的有效性。其次,进一步针对分配梁构造下巨型钢管混凝土柱的屈服承载力、极限承载力进行参数分析,共考虑47种分配梁截面,涵盖5种不同截面尺寸的巨型柱。结果表明,由分配梁构造传递至核心混凝土的竖向荷载,屈服承载力略大于分配梁自身的全截面抗剪承载力,极限承载力小于分配梁自身的全截面抗拉极限承载力。同时,明确了分配梁受力机理及破坏模式。最后,为模拟分配梁构造在实际工程中的性能,建立设置分配梁的十四层足尺钢管混凝土巨型柱精细化有限元计算模型并对其共同工作性能进行分析,表明采用该构造能够基本保证巨型钢管混凝土柱中钢管与混凝土的平截面假定共同工作状态。In order to study the cooperating performance between steel tube and core concrete in the joints between largesection CFT giant columns and transferring girders or trusses in super high-rise buildings, a new detailing named distributive beam is suggested by authors. The cooperating behavior between core concrete and steel tube in CFT giant columns with distributive beam detailings in beam-column joints was numerically investigated based on the test results. For further numerical analysis of the tested specimens, a refined finite element （FE） model using ABAQUS is developed to compute the axial load-axial deformation relationship, failure mode of specimens and percentage of the load shared by the concrete. The analysis results agree well with the test ones, which validate the correctness of the FE model. Parametric analysis is conducted on beams with 47 kinds of sections and large-section CFT columns with 5 kinds of crosssections. It can be concluded that the yield capacity of distributive beam is larger than the full cross-section shear strength of the beam, while the ultimate capacity is below the full cross-section tensile strength. Meanwhile, the mechanic behavior and load transfer mechanism of distributive beam is also analyzed. Finally, a finite element model of 14-storey large-section CFT column is established and to evaluate the cooperating performance of large-section CFT columns with distributive beams in a possible practical project. The analysis results indicate that the plane section assumption can be fulfilled by setting the distributive beam detailings.

关 键 词：钢管混凝土巨型柱 分配梁 轴压承载力 共同工作 数值计算 

分 类 号：TU392.1[建筑科学—结构工程] TU317.1