梁端加盖板节点域箱形加强式工字形柱弱轴连接边框架节点滞回性能的有限元分析

发布时间：2018-06-14 11:46

本文选题：弱轴连接 + 蒙皮板　；参考：《长安大学》2015年硕士论文

【摘要】：节点域箱形加强式工字形柱弱轴连接作为一种新型的连接形式,在单调荷载试验中已被证明具有良好的力学性能,为进一步探究其在循环荷载下的力学性能,本文进行了边框架节点在低周反复荷载作用下的ABAQUS有限元模拟研究。本文重点研究了标准型节点和盖板加强型节点,通过一系列有限元的变参数分析和数据处理,研究了节点和关键构件的破坏机理、连接焊缝的应力分布、M??曲线、刚度分类、刚度和延性的匹配等问题,同时还针对盖板加强型节点的不足进行了改进分析。得到的结论主要如下:1.标准型节点和盖板加强型节点均能达到强节点域的特点,在有侧移框架中均属于半刚性连接,两种节点的梁翼缘连接焊缝处的应力沿梁宽方向均呈现不利的V型分布;盖板可以控制塑性铰远离连接处,能显著提高节点的初始转动刚度和承载力,并有着较为理想的延性和耗能能力。2.节点在较高的轴压比下有成为强柱弱梁的趋势,并且抗震性能也会大大劣化,新型连接节点的轴压比应控制在0.6以内;3.相对于高度,蒙皮板的厚度对节点的刚度和延性有更直接和明显的影响,应保证最小的蒙皮板厚度来确保节点具有足够的转动刚度和塑性转动能力。3.盖板长度和厚度对节点性能影响较大,过大或过小都会降低节点的抗震性能,研究证明盖板长度和厚度分别取0.5倍的梁截面高度和翼缘厚度时,节点的性能较为理想;4.梁的刚度增大会提高节点的承载力,柱的刚度增大则会提高节点的转动刚度,因此,梁柱线刚度比应该控制在一定的范围内;5.由于蒙皮板形成的箱形构造使节点域大大加强,因此,柱子绕强轴弯曲不会明显降低弱轴连接的受力性能,存在强轴连接,弱轴连接仍然有较好的抗震性能。6.梁翼缘板式连接可以明显减小梁翼缘连接焊缝的尺寸,并能显著的改善连接焊缝边缘处的应力集中;而在蒙皮板后加焊竖向隔板可以增强节点的刚度,放松对蒙皮板厚度的要求,其也能促使应力从连接焊缝的边缘向中间区域转移;最后,对本文内容的后续研究进行了展望,给出了后续研究的内容及方向。
[Abstract]:As a new type of connection, the box reinforced I-shaped column weakly connected in nodal domain has been proved to have good mechanical properties in monotone load tests, in order to further explore its mechanical properties under cyclic load. In this paper, Abaqus finite element simulation of edge frame joints under low cyclic loading is carried out. This paper focuses on the study of standard joints and slab reinforced joints. Through a series of finite element variable parameter analysis and data processing, the failure mechanism of joints and key components is studied, and the stress distribution of weld joint is analyzed. The problems of curve, stiffness classification, stiffness and ductility matching are also analyzed. The main conclusions are as follows: 1. Both the standard joint and the strengthened cover joint can achieve the characteristics of strong joint domain. They are semi-rigid connections in the frame with lateral displacement, and the stress distribution of the weld seam at the flange joint of the two kinds of joints is unfavorable along the beam width direction. The cover plate can control the plastic hinge far away from the joint, can significantly improve the initial rotational stiffness and bearing capacity of the joint, and has an ideal ductility and energy dissipation capacity of .2. The joint has the tendency to become a strong column and weak beam at higher axial compression ratio, and the seismic performance will deteriorate greatly. The axial compression ratio of the new connection should be controlled within 0.6 ~ 3. Compared with the height, the thickness of the sheathed plate has more direct and obvious influence on the stiffness and ductility of the joint. The minimum thickness of the sheathed plate should be ensured to ensure that the joint has sufficient rotational stiffness and plastic rotation ability. The length and thickness of cover plate have a great influence on the performance of the joint, too large or too small will reduce the seismic performance of the joint. It is proved that when the length and thickness of the cover plate are 0.5 times the height of beam section and the thickness of flange respectively, the performance of the joint is better than that of the joint. The stiffness of the beam will increase the bearing capacity of the joint, and the stiffness of the column will increase the rotational stiffness of the joint. Therefore, the Liang Zhu line stiffness ratio should be controlled within a certain range of 5. Due to the box structure formed by the sheathed plate, the joint domain is greatly strengthened, so the bending of the column around the strong axis does not obviously reduce the mechanical properties of the weak axis connection, and there is a strong axis connection, and the weak axis connection still has good seismic performance. 6. The beam-flange plate connection can significantly reduce the size of the beam-flange joint weld seam, and can significantly improve the stress concentration at the weld edge of the beam-flange connection, and the stiffness of the joint can be enhanced by adding the welded vertical diaphragm after the sheathed plate. Relaxation of the thickness of the skin plate can also promote the stress transfer from the edge of the weld joint to the middle zone. Finally, the future research of this paper is prospected, and the content and direction of the follow-up research are given.
【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU391

【共引文献】