复式钢管混凝土柱—钢梁节点力学性能研究

发布时间：2018-01-13 08:29

本文关键词：复式钢管混凝土柱—钢梁节点力学性能研究　出处：《长安大学》2013年博士论文　论文类型：学位论文

【摘要】：复式钢管混凝土柱具有较高抗压承载力，在强地震作用下能体现出很好防倒塌能力，可将其用于大跨度桥梁或超高层房屋建筑中。内圆外方的复式钢管混凝土柱同时兼有整洁美观及节点构造简便等特点，故在工程中日益受到重视。然而，目前国内外对复式钢管混凝土柱-钢梁连接节点的研究较少，阻碍了复式钢管混凝土柱结构的发展应用，所以有必要研究新型复式钢管混凝土柱-钢梁节点的设计方法及抗震性能。综合我国现状及目前钢管混凝土柱节点的研究成果，本文设计了一种新型复式钢管混凝土柱与钢梁的连接节点形式，对其进行了低周往复荷载试验，同时采用数值模拟及理论分析相结合的方法对此类新型节点进行深入研究，主要研究内容和取得的成果如下：本文对6个新型复式钢管混凝土柱-钢梁节点试件和1个单钢管混凝土柱-钢梁节点试件进行了低周往复荷载作用下的试验研究，此类新型节点的传力构件包括锚固腹板、水平端板、连接板及竖向肋板。结果表明：竖向肋板外伸长度可有效调节节点破坏时塑性铰位置，锚固腹板加肋可有效提高节点承载力；此类新型复式钢管混凝土柱-钢梁节点的破坏模态基本为水平端板与钢梁翼缘连接处出现塑性铰破坏；复式钢管混凝土柱节点与方钢管混凝土柱节点相比，承载力较高、耗能能力强、刚性和延性均较好，适用于抗震设防区的钢管混凝土结构中。采用有限元分析软件ABAQUS对新型复式钢管混凝土柱-钢梁节点模型进行非线性有限元分析。数值分析得到的滞回曲线、骨架曲线及节点破坏模态与试验结果吻合良好，证明了有限元模型在选取单元类型、材料本构及破坏准则方面的合理性。在此基础上，对复式钢管混凝土柱-钢梁节点进行了应力分析，，此类新型节点传力路径明确，在高轴压比作用下具有良好的工作性能，锚固腹板加肋传递节点应力的能力更好。在数值模型的基础上，对典型节点试件SBJ2-2进行系统参数分析。对比了梁端加载方式与柱端加载方式对节点破坏模态的影响；确定出竖向肋板与锚固腹板的合理高度；得出了各组参数下节点的弯矩-转角曲线及对应的节点初始刚度曲线；采用三参数幂模型建立了此新型节点的弯矩-转角实用计算式，拟合出节点的初始刚度计算式；根据节点弯矩-转角计算式所得结果与试验、数值模拟结果进行对比，吻合良好。本文建立的节点弯矩-转角全过程计算式可评价各个设计参数对节点受力的影响程度，为此类新型节点的工程设计奠定理论基础。研究此类新型复式钢管混凝土柱-钢梁节点的抗剪受力性能。考虑节点在竖向轴力和梁端往复荷载作用下，钢管柱壁的环向拉应力对抗剪承载力的削弱作用；节点域的钢材采用抗剪三折线模型，内外层混凝土采用上升段和水平段抗剪模型，将各部分叠加建立了此类新型节点的抗剪承载力计算式；其中外方钢管腹板与竖向肋板对节点抗剪承载力的贡献值较大；将抗剪承载力计算结果与试验结果进行对比，两者吻合良好，从而验证了此类新型节点抗剪承载力计算方法的正确性。
[Abstract]:With the bearing capacity of composite concrete-filled steel tube column with high compressive strength, can reflect the good ability of anti collapse under strong earthquake, which can be used for long-span bridges or high-rise buildings. Composite concrete-filled steel tube column inside the circle of both neat and simple structure nodes and other characteristics, so in engineering more and more attention.
However, the current domestic and foreign research on composite concrete-filled steel tube column steel beam joint less hindered the development of the application structure of composite concrete-filled steel tube column, so it is necessary to study the new design method of composite concrete-filled steel tube column steel beam joints and seismic performance. Research results of China's present situation and the concrete filled steel tubular column joints in this paper. The design of the connection form a new composite concrete-filled steel tube column and steel beam, the low cyclic loading tests are carried out on it at the same time, in-depth study of these new nodes by the analytical method of numerical simulation and theory, the main research contents and achievements are as follows:
In this paper, 6 new composite concrete-filled steel tube column steel beam joints and 1 single CFST column and steel beam joint specimens were studied under low cyclic loading, the force transmission component of this new type of node including anchorage webs, horizontal end plate, a connecting plate and a vertical rib plate. The results show that: the vertical rib extending length can effectively adjust the node failure location of plastic hinge, anchorage webs with ribs can effectively improve the bearing capacity of the joint; the failure mode of this new type of composite concrete-filled steel tube column and steel beam joint is the basic level of the end plate and steel beam flange connections are plastic hinge failure; compared to the connections of multibarrel tube confined concrete column joints and square concrete filled steel tubular column, high bearing capacity, energy dissipation capacity, rigidity and ductility are good, concrete filled steel tube structure is suitable for seismic zone.
Using finite element analysis software ABAQUS, the nonlinear finite element analysis of the new type of composite concrete-filled steel tube column and steel beam joint model. Numerical analysis of the hysteretic curves, skeleton curves and the joint failure modes agree well with the experimental results, proved that the finite element model in the selection of element type, the rationality of material constitutive model and failure criterion in this paper. On the stress analysis of composite concrete-filled steel tube column and steel beam joint, force of the new type of connection path is clear, with high axial compression ratio has good performance under the action of anchorage webs with ribs transfer node stress better.
Based on the numerical model of the specimen SBJ2-2 system parameters analysis. Comparison of the effects of beam end loading and column end loading on the joint failure mode; determine a reasonable height of vertical ribs and anchorage webs; stiffness curve joint initial bending moment - the parameters of nodes and the corresponding rotation angle curve the calculation formula of the rotation moment; this new node is established using the three parameter power model, fitting the calculated stiffness of the initial node type; the calculation results and test according to the nodal moment rotation, numerical simulation results are compared. The formula can be in good agreement with the effect of design parameters to evaluate various stress the whole process of node joint moment - this angle, lay the theoretical foundation for the new type of connection design.
The shear properties of this new type of composite concrete-filled steel tube column and steel beam joint. Considering the effect of axial force and vertical nodes in the beam under cyclic loading, steel column wall circumferential tensile stress shear weakened capacity; the node domain is used for steel shear three line model, the inner and outer concrete rise section and horizontal section shear model, each part was built by superimposing the new type of connection of the shear bearing capacity formula; the foreign steel webs and the vertical ribs on the shear resistance contribution value is bigger; the shear capacity calculation results were compared with experimental results, good agreement, which proved to be correct the calculation method for the shear bearing capacity of the new type of connection.

【学位授予单位】：长安大学
【学位级别】：博士
【学位授予年份】：2013
【分类号】：TU398.9

【引证文献】