节点域箱形加强式工字形柱弱轴盖板加强连接的抗震破坏机理及设计对策

发布时间：2018-06-08 03:32

本文选题：钢框架 + 弱轴连接　；参考：《长安大学》2017年硕士论文

【摘要】：节点域箱形加强式工字形柱弱轴连接是按照高延性和高承载力的抗震设计思想,针对工字形柱钢框架弱轴连接设计提出的一种新型连接构造形式,依据前期边框架节点的试验研究和有限元分析证实了这种连接具有良好的抗震性能。采用新型梁柱弱轴连接的工字形柱钢框架比箱形柱钢框架相比更具有良好的经济性。本文对节点域箱形加强式工字形柱弱轴盖板加强连接节点进行循环加载试验研究,分析了节点试件的破坏模式、滞回性能、延性及耗能能力等抗震性能。采用ABAQUS建立考虑损伤的有限元模型并进行非线性分析,分析了节点的关键影响参数并确定参数的合理取值。依据试验研究与有限元分析提出了针对此类型节点的设计方法,并结合实际工程验证节点设计方法的合理性与可靠性。试验与有限元研究结果如下:(1)新型梁柱弱轴盖板加强连接节点能够实现塑性铰的外移,避免了梁翼缘连接焊缝过早发生脆性断裂破坏。节点的滞回曲线呈现较为饱满的梭形,具有良好的耗能能力,但焊缝的开裂导致节点的位移延性系数低于3.0。(2)节点域在节点受力过程中发生弹性剪切变形,节点域处应力基本处于弹性阶段,新型梁柱弱轴连接节点具有明显的“强节点域”特征。(3)蒙皮板厚度对节点的抗震性能具有明显的影响作用。在节点设计时,应保证节点蒙皮板厚度的取值满足蒙皮板最小厚度的设计要求。(4)加强盖板的形状对节点的抗震性能影响较小,设计时可优先选取矩形加强盖板,而加强盖板的长度和厚度对节点的抗震性能具有明显的影响作用。建议加强盖板的取值范围为:加强盖板的长度取梁高的0.5~0.7倍,加强盖板的厚度应大于等于梁翼缘厚度的0.5倍且大于等于6mm。(5)梁柱线刚度比的变化对节点的抗震性能具有明显的影响作用,但梁线刚度和柱线刚度的变化对节点抗震性能的影响规律和程度相差较大。建议节点的梁柱线刚度比应小于等于1.5。(6)提出了新型梁柱弱轴盖板加强连接节点的设计方法,节点设计方法经验证是合理可靠的,可为此类型节点的工程应用提供设计参考。
[Abstract]:The box reinforced I-shaped column weak axis connection in the joint domain is a new type of connection structure, which is based on the seismic design idea of high ductility and high bearing capacity, aiming at the weak axis connection design of I-shaped column steel frame. According to the experimental research and finite element analysis, the joint has good seismic performance. The I-shaped column steel frame with a new type of Liang Zhu weak axis connection is more economical than the box column steel frame. In this paper, cyclic loading tests are carried out on the connection joints with box reinforced I-shaped columns in the joint domain. The failure mode, hysteretic performance, ductility and energy dissipation capacity of the joints are analyzed. The finite element model considering damage is established by Abaqus and the nonlinear analysis is carried out. The key parameters of the node are analyzed and the reasonable values of the parameters are determined. Based on the experimental research and finite element analysis, the design method for this type of joint is proposed, and the rationality and reliability of the design method are verified by the actual engineering. The experimental and finite element results are as follows: (1) A new type of Liang Zhu weak axle cover plate can realize the plastic hinge's outward displacement and avoid the premature brittle fracture failure of the beam-flange joint weld. The hysteretic curve of the joint presents a full fusiform shape with good energy dissipation ability, but the crack of the weld seam leads to the displacement ductility coefficient of the joint being lower than 3.0.2.) the elastic shear deformation occurs in the joint domain during the process of the joint loading. The stress in the joint region is basically in the elastic stage, and the thickness of the sheathed plate has obvious influence on the seismic behavior of the joint. The new type of Liang Zhu weakly connected joint has the characteristic of "strong joint domain". In the design of joints, it is necessary to ensure that the value of the thickness of the joint skin plate meets the design requirements of the minimum thickness of the skin plate) the shape of the strengthened cover plate has little effect on the seismic performance of the joint, and the rectangular reinforced cover plate can be selected first in the design. The length and thickness of the strengthened slab have a significant effect on the seismic performance of the joints. It is suggested that the value range of the strengthened cover plate is: the length of the strengthened cover plate is 0.5 ~ 0. 7 times the height of the beam, The thickness of the strengthened slab should be greater than 0.5 times of the thickness of the flange of the beam and greater than or equal to 6mm. 5) the change of the stiffness ratio of the Liang Zhu line has an obvious effect on the seismic behavior of the joints. However, the influence of beam line stiffness and column stiffness on the seismic behavior of joints varies greatly. It is suggested that the Liang Zhu line stiffness ratio of the joint should be less than or equal to 1.5.56) A new design method of the Liang Zhu weak shaft cover plate reinforced joint is proposed. The design method of the joint is proved to be reasonable and reliable, which can be used as a design reference for the engineering application of the type of joint.
【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU391;TU312.3

【参考文献】