具有拼接钢主梁的钢混双面组合梁受力性能研究

A Study of the Mechanical Behavior of the Double-Deck Steel-Concrete Composite Beam with Main Spliced Steel Girders

研究对象为具有拼接钢主梁的钢与混凝土双面组合连续梁,钢主梁段采用翼缘板和腹板盖板由高强螺栓拼接。理论分析了拼接截面的弹性、塑性极限承载力及其受力变形特征;通过有限元分析软件ANSYS建立拼接节点的实体模型,得到拼接节点的弯矩转角曲线。依据得到的拼接节点本构关系,分别建立拼接钢主梁的两跨连续组合梁和无拼接的两跨连续组合梁的有限元模型,分析对比二者的变形能力及承载性能:当荷载较小时,两种不同拼接方式的连续组合梁具有相同的结构刚度;随荷载的增加,克服高强螺栓提供的摩擦力后,拼接节点开始表现出半刚性特性,拼接组合梁刚度将逐渐减小。结果表明,在满足组合梁结构强度和刚度的前提下,合理的钢主梁半刚性连接设计可用来增强组合梁结构的变形能力。结论可供高强螺栓拼接钢主梁的钢与混凝土组合梁设计计算参考。

The paper aims at studying the mechanical behavior of a double-deck steel-concrete composite beam with main spliced steel girders,both the flange slabs and cover slabs of which are joined together with high-strength bolts. Theoretically analyzed in the paper are both the elastic and plastic limits of bearing capacity and the deformation characteristics of the joints. Secondly, the moment rotation curve of the joint is obtained by the solid model with the help of the FE analysis software of ANSYS. Based on the obtained constitutive relations of the spliced joints, the finite element models for the two spans of continuous composite beams with or without a main spliced steel girder are respectively established, with their deformation capability and bearing performance analyzed and compared. When the load is comparatively small, both the continuous composite beams joined together in two different ways are equal in structural stiffness. With the load increased,and after the friction provided by the high-strength bolts is overeomed, the joined joints begin to show the semi-stiff property, and the stiffness of the joined composite beam begins to decrease gradually. The result shows that in the premise of meeting the requirements for the composite beam in both strength and stiffness,the rational semi-rigid joining design for the main steel girder may be used to improve the structural deformation capability of the composite girder larger capacity of deformation. The paper may serve as a useful references for the design of and calculations for steel-concrete composite beams with main steel girders joined together with high-strength bolts.