主管灌混凝土的钢管结构K型搭接节点滞回性能研究

发布时间：2019-04-20 13:31

【摘要】：钢管结构因其轻质高强、材料延性好及良好的滞回性能等特点,是最常采用的建筑结构形式之一。节点作为钢管结构的重要组成部分,同时也是结构耗能的关键部位,对节点性能的研究是钢管结构研究发展的基础。相对节点静力性能方面的研究,对钢管节点滞回性能的研究相对较少,尤其对钢管结构主管灌混凝土的加强节点滞回性能的研究处于起步阶段。基于此,本文对钢管结构主管灌混凝土的加强型K节点抗震破坏机理进行试验研究,共对6个钢管结构K型搭接节点试件开展拟静力试验,并通过有限元软件分析与拟静力试验数据进行比较分析。主要的研究工作如下:(1)加强型K型搭接节点的模型建立。通过试验前期的预分析,将焊缝模拟引入K节点的模型建立,对关键参数进行确定,分析节点的静力性能,确定试验节点试件的几何参数,为试件的试验加载做好准备工作。(2)加强型K节点的拟静力试验研究。设计了 6个钢管结构加强型K型搭接节点试件,在两支管端通过伺服作动器实现低周往复轴向荷载,考察节点的破坏机理。试验表明,未加强试件其主要破坏模式为主管管壁的塑性破坏,而通过主管灌混凝土加强的试件,其主要破坏模式为主管管壁的拉裂破坏并且伴随有受压支管的轻微屈曲。通过比较两者破坏模式,得出主管灌混凝土的加强方式,可以改变节点的破坏模式,抑制主管的塑性失效破坏,有效的提高节点承载力和承载效率。(3)主管灌混凝土的钢管结构K型搭接节点滞回性能量化评价。基于试验结果,通过对加强型K型搭接节点的滞回分析,表明未加强K型搭接节点和通过主管灌混凝土加强的K型搭接节点均具有较好的滞回性能,可以满足结构的抗震要求;主管内灌混凝土的加强方式在一定程度上限制了节点的塑性发展,降低了节点的延性和滞回性能,但提高了节点的刚度,可以有效增大试件的极限承载力。另外通过比较两种不同的加强方式,在滞回性能方面两者差别不大,表明采用粉煤灰混凝土可以很好的替代传统混凝土用于钢管结构局部加强。(4)加强型K型搭接节点有限元滞回性能分析。用有限元分析软件ANSYS对节点进行滞回性能模拟分析,通过有限元模拟结果与拟静力试验比较,得出节点破坏模式与试验结果相符,滞回曲线也与试验结果吻合,但是承载力偏大。说明可以采用有限元软件对节点试件进行参数分析。
[Abstract]:Steel pipe structure is one of the most commonly used building structures because of its light weight and high strength, good ductility and good hysteretic performance. As an important part of the steel pipe structure, the joint is also the key part of the energy dissipation. The research on the joint performance is the foundation of the research and development of the steel pipe structure. Relative to the static performance of the joints, the hysteretic behavior of steel pipe joints is relatively few, especially for the study of the hysteretic behavior of reinforced joints filled with concrete in the main pipe structure is still in its infancy. Based on this, the anti-seismic failure mechanism of reinforced K-joints of steel tube structure is studied in this paper, and the pseudo-static tests are carried out on six K-type lap joints of steel tube structures. And through the finite element software analysis and the pseudo-static test data to carry on the comparison analysis. The main research work is as follows: (1) the model of strengthened K-type lap joints is established. Through the pre-analysis of the pre-test, the welding seam simulation is introduced into the K-node model, the key parameters are determined, the static performance of the joints is analyzed, and the geometric parameters of the test joints are determined. Prepare for the test loading of the specimen. (2) quasi-static test study of the strengthened K-joints. Six specimens of reinforced K-type lap joints of steel pipe structures were designed to realize low circumferential reciprocating axial loads on two pipe ends by servo actuators. The failure mechanism of the joints was investigated. The results show that the main failure mode of the unreinforced specimen is the plastic failure of the main pipe wall, while the main failure mode of the specimen strengthened by the main pouring concrete is the tensile crack failure of the main pipe wall, accompanied by slight buckling of the compressed branch pipe. By comparing the two failure modes, it is concluded that the strengthening mode of the main pouring concrete can change the failure mode of the joint and restrain the plastic failure of the supervisor. The bearing capacity and bearing efficiency of joints are improved effectively. (3) quantitative evaluation of hysteretic behavior of K-type lap joints of steel tube structures filled with concrete is carried out. Based on the experimental results, the hysteretic analysis of the strengthened K-lap joint shows that both the K-type lap joint and the K-type lap joint strengthened by the main pouring concrete have better hysteretic performance and can meet the seismic requirements of the structure. To a certain extent, the strengthening mode of the inner-filled concrete in the pipe limits the plastic development of the joint, reduces the ductility and hysteretic performance of the joint, but increases the stiffness of the joint and can effectively increase the ultimate bearing capacity of the specimen. In addition, by comparing two different reinforcement methods, there is no significant difference in hysteretic performance between the two methods. It is shown that fly ash concrete can be used to replace traditional concrete for local strengthening of steel tube structures. (4) finite element hysteretic performance analysis of reinforced K-type lap joints. Finite element analysis software ANSYS is used to simulate the hysteretic performance of the joints. Comparing the finite element simulation results with the pseudo-static tests, the results show that the failure mode of the joints is consistent with the experimental results, and the hysteretic curves are also consistent with the experimental results. But the bearing capacity is too large. It shows that the finite element software can be used to analyze the parameters of the joints.
【学位授予单位】：宁夏大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU392.3

【参考文献】