摘要: 框架-支撑结构体系在抗震设防地区的应用中有很大的优势,因为其构造简单且具有较强的抗侧刚度。斜向布置的支撑能够显著的减小结构的水平位移,改善结构的内力分布。但是在往复的水平地震作用下,支撑很容易产生侧向屈曲,随着结构的受压进入到弹塑性阶段时,结构的抗侧刚度和楼层抗剪能力都会急剧下降,层间位移骤增,会导致结构整体失稳破坏。防屈曲耗能支撑则是一种性能优良的新型耗能减震构件,它在普通支撑的基础上得到了改进。在小震作用下,它像普通支撑一样,能提供给结构足够的抗侧刚度,在大震作用下,除了能保证结构抗侧刚度满足要求的同时,还能吸收耗散地震能量,起到保护主题框架结构安全的作用。本文首先阐述了防屈曲耗能支撑的研究背景、构造原理、优缺点及其研究现状,从理论上分析了防屈曲耗能支撑构件的稳定性设计方法,确定了支撑构造部分参数的选取,得出了防屈曲耗能支撑疲劳寿命的计算公式。其次采用通用有限元软件ANSYS对十字形截面防屈曲耗能支撑构件进行了数值模拟分析,分析了支撑的构造参数如约束刚度和内核单元初始缺陷对防屈曲耗能支撑的耗能性能的影响,并给出了各个参数的合理值。最后运用有限元结构软件对防屈曲耗能支撑框架进行了分析。42342
毕业论文关键词:抗侧刚度;失稳;防屈耗能曲支撑;耗能性能;
Abstract:Framework-braced structure system have a lot of advantages in the application inseismic regions. Because its structure is simple, and it has strong lateral stiffness. Slanting braced can effectively reduce the horizontal displacement of the structure, and improve the internal force distribution of the structure. But under the reciprocating horizontal earthquake action,the braced is easy to appear lateral buckling. With the structure entering into elastic-plastic stage, the lateral stiffness of the structure and floor shear capacity drop sharply,and the interlayer displacement jump. The whole structure will be destroyed Buckling-Restrained Brace (BRB) is a kind of new energy dissipation component with high performance. It is improved on the basis of general brace. Under the effect of small earthquakes, it is the same as general brace. They can provide enough lateral stiffness to the structure. While under the strong earthquakes, BRBs can not only ensure structural lateral stiffness meeting the requirements, but also absorb energy of earthquake. They play a role to protect the safety of main frame structure.This article expounds the research background, structural principle, the adventages and disadvantages and research status of the BRB firstly. Also it analyzes the design method of stability in theory, and confirms the different part parameters. We can obtain the calculation formula of fatigue life of BRB from the article at the same time.Secondly, we analyze the cross section BRB component with ANSYS,a kind of general finite element software. Then we confirm that different part parameters such as constraint stiffness, clearance, connecting section stiffness and initial defects of the kernel unit have different influence to the performance of the BRB,and we get the reasonable value of each
parameter.Last, the elastic-plastic comparative analysis among pure steel frame, the general brace frame and cross section BRB frame is studied with SA02000, another finite element structure software. The analysis results show that: under the effect of small earthquakes,BRB plays the same pole as general brace in the framework, and they can effectively reduce the structural responses; but under strong earthquakes, the BRB begins to enter the yield stage and consume part of seismic energy through the deformation of the kernel unit. It can ensure the safety of main frame structure better.
Keywords: resistant-lateral rigidity; buckling; Buckling- Restrained Brace; energy-intensive performance; structural response 新型受压可屈曲智能型钢棒支撑有限元分析研究:http://www.751com.cn/gongcheng/lunwen_42751.html