【作者】 刘佳；

【导师】 董宏英；

【作者基本信息】 北京工业大学 ， 结构工程， 2008， 硕士

【摘要】 门式刚架是轻钢结构体系的典型代表,广泛应用于单层工业厂房和民用建筑中。目前,门式刚架是按照节点连接为刚性的假定进行设计,没有考虑端板连接的半刚性对其性能的影响。半刚性连接不但对节点自身的受力性能产生影响,而且对门式刚架整体结构的内力及位移也产生影响。目前的研究仅对这些问题提出了一些合理性建议,但在结构设计中如何合理的把半刚性连接对结构性能的影响考虑进去,这些建议不够全面。围绕这一问题,本文对门式刚架结构的特点进行了深入的探讨和研究。本文首先系统地归纳了各国现行规范中关于端板连接的设计方法。在对比我国规范算法的基础上,提出基于“T型件”的节点改进设计方法,并引用某工程实例,运用此法对端板连接节点重新进行优化方案设计,结果证明此方法是准确可靠、简单可行的,而且能使设计更经济。接着在半刚性理论研究方面,本文从有限元理论的高度推导了半刚性节点局部坐标下的单元刚度矩阵和单元刚度方程、以及整体坐标系下的总刚度方程,并利用ANSYS有限元软件对高强螺栓端板连接节点的高度非线性和复杂接触进行数值模拟分析,经与相关文献对比,对其受力性能有了新的认识。最后,本文利用ANSYS APDL语言编程对不同柱脚约束条件下节点刚接、半刚接以及铰接的变截面门式刚架进行大量的建模计算,探讨了端板连接节点的半刚性对门式刚架位移和内力以及用钢量的影响,通过结果分析,分别从节点形式和构造措施两方面,获得了提高节点刚度的认识,提出了一些对工程设计具有一定的参考价值的结论与建议,同时也为进一步的研究该种节点的连接性能打下了基础。更多还原

【Abstract】 As the typical representation of light-weight steel structure, portal frame is being widely adopted in single-story industrial plants and civil architectures. At present,design of portal frame is performed in terms of rigid joint connection hypothesis, and the effects of semi-rigid feature of end-plate connection on erformance of portal frame are not considered. Semi-rigid connection affects not only load-bearing performance of joint itself but also internal force and displacement of general portal frame structure.According to these problems, some reasonable suggestions are proposed in present study, but they are not comprehensive when it comes to how to take consideration of the effect of semi-rigid connection on structure performance during process of structural design.Aimed at the point, the haracteristics of portal frame are discussed and studied.At first, In this paper, the design methods about end-plate connection of the present oversea and domestic codes are concluded systematically.Based on the contrast with domestic calculation method, it proposes design method of joint-improving based on“T style part”, cites a project example, and use this method to optimize the design of the end-plate connection secondly, with the result confirming that this method not only correct, reliable,simple, feasible but also economic to the design.In succession,on the research of semi-rigid theory, the element stiffness matrix and element stiffness equation under local coordinate, and global stiffness equation finite element under global coordinate of semi-rigid connections are derived at the height of finite element theory in this paper. It also analyzes the highly nonlinearity and complex contact of the high-strength bolt end-plate connection joints with numerical simulation, in contrast with relative literature,and gets new cognition of load-bearing performance.Finally,in this paper, lots of modelings and analysis of variable section portal frame with rigid, semi-rigid and hinged joints under the different constraint conditions of column base have been carried out in ANSYS APDL language, and the effects of internal force and displacement of portal frame structure by semi-rigidity of end-plate connections. Through the analysis of results,on the two aspects of joint forms and construction measures respectively, the cognition of improving joint stiffness is obtained and it gives valuable conclusion and suggestion to construction design, also make a foundation for further study of connection performance of this kind.更多还原