【作者】 王万建；

【导师】 郭秉山；

【作者基本信息】 西安科技大学 ， 结构工程， 2004， 硕士

【摘要】 钢框架依其自重轻、工程造价低、有效使用面积大、施工速度快和投资效益高等综合优势，在国外普遍采用，在国内也正高速发展。丧失稳定一直是钢结构破坏的主要形式之一，所以稳定性分析是钢框架设计中的一个重要环节。尤其是在当前，由于结构设计理论和材料性能的发展，使结构更趋于轻薄化，对钢框架进行稳定性分析的重要性更为突出。现行框架柱的稳定设计是建立在对偏心压杆的二阶弹性分析基础之上、以放大一阶弯矩的形式表达的设计方法，而有侧移框架的失稳则是在材料的弹塑性性能发展到一定程度之后才发生的。钢框架模型实验说明，建立在有限数值积分基础上的二阶弹塑性分析在整个受力和变形过程中与实验结果有较好的一致性，其结果较真实地反映了框架的极限承载能力。　本文采用传递矩阵法对平面钢框架结构进行了整体弹塑性稳定分析。利用弹塑性铰模型，推导出反映杆件两端弹塑性状态变量的梁单元传递矩阵、柱单元传递矩阵以及反映各种支座处内力和位移突变的支座处的传递矩阵，得出了求解单层框架结构弹塑性屈曲荷载的微分方程。利用总体传递矩阵求出框架顶部节点水平侧移和荷载一一对应值，得到钢框架的极限承载力。在应用传递矩阵法对钢框架进行弹塑性稳定分析中，考虑了杆件初弯曲、初偏心和残余应力以及框架侧移引起的 Ｐ–Δ效应对钢框架稳定性的影响。根据上述思想，本文运用矩阵运算功能非常强大的 ＭＡＴＬＡＢ 编制了相应的计算程序，并通过几个算例进行了分析和比较，结果表明，用弹塑性铰模型与传递矩阵法相结合分析单层平面钢框架的整体弹塑性稳定是一种较好的方法，具有精确度高、力学概念清晰、编制程序简单等优点。更多还原

【Abstract】 Steel frames are used widely abroad and applied greatly in our country withcomprehensive such as light weight, low project expense, more effective-used area ofbuildings, less construction stage and high capital mileage etc. Losing stability is always oneimportant factor of damage of steel frames. Stability analysis is one important part in thecourse of steel frames design. Especially nowadays, structures trend to light-thin modelbecause of the development of design theory and material property. It is a highlight that steelstructures total stability is calculated. Stability design method of frame column currently ineffect is based on the second-order elastic analysis of bias pressure staff and is expressed byamplifying one-order moment. But, losing stability of frames with side displacement occurswhen the elastic-plasticity of stuff develops to some level. The in-plane stability test on theinelastic steel frames proves that the second-order inelastic analysis is a better method ofdetermining the ultimate capacity of frames. In this paper, Transfer Matrix Method is introduced to study total elastic-plastic stability ofsteel frames. Making use of elastic-plastic numerical model, Beam-element ,column-elementtransfer matrix that indicate elastic-plastic state parameters of two ends of bars and transfermatrix that indicates internal force and displacement variety off every braces are derived inthis paper. The total transfer matrix that solves bucking load of frames is obtained. The valuesof top-story horizontal displacement and loads can be obtained by use of the total transfermatrix. So, the ultimate load can be obtained. The effects on steel frames stability of initialflexure ,initial bias ,residual stress and P-Δ effect that is brought by the displacement offrames are included in the course of stability analysis of steel frames by transfer matrixmethod . By the idea, the corresponding computation program is written with MATLABwhose function in dealing with matrix is very big. The analysis and comparison of someexamples indicates that the method the text suggested is effective in studying totalelastic-plastic stability of one-story plane-steel frames, with high degree of accuracy, clearmechanical concept and convenient programming.更多还原