A new theoretical model to evaluate the moment-rotation (M-) elationship for stiffened and extended steel beam-column end-plate connections has been derived in this paper. Based on a specific definition of the end-plate connection rotation, the end-plate connection is decomposed into several components, including the panel zone, bolt, end-plate and column flange. The complete loading-deformation process of each component is then analysed. Finally the loading–deformation process for the whole connection is obtained by superimposing the behaviour of each component. In addition, 5 joint tests have been conducted to verify the proposed analytical model. By comparing it with the test results, it has been concluded that this analytical model can evaluate the rotational behaviour of end-plate connections, as well as the moment-rotation (M-) curve and the initial rotational stiffness accurately. Furthermore, it can analyse every contribution to the joint's rotational deformation, such as the shear deformation of the panel zone, the bolt extension, the bending deformation of the end-plate and column flange, etc. This analytical model also provides moment-shear rotation (M-s) and moment-gap rotation (M-ep) curves, which establish a reliable foundation for analysing the detailed rotational behaviour of end-plate connections.

单层索网体系是点支式柔性支承玻璃幕墙结构中的一种新型体系，以其僵筑结构简捷、轻盈美观、通透性好等优点深受许多建筑师的青睐，应用前景广泛。由于采用了柔性索杆，它的设计方法不同于其他一般的幕墙结构,除满足结构强度、刚度、变形要求外，还要考虑预应力和几何非线性问题。结合单层索网柔性支承体系在国内外幕墙工程中的应用,阐述了该体系的受力特点、研究现状和存在的问题，并对其设计分析和施工技术中的主要问题进行了探讨。

空间管节点几何构形多样，受力复杂，影响其承载性能的因素较多，本文采用有限元软件ANSYS，选用SHELL181壳体单元建模计算，并考虑了焊缝的影响，分析了荷载路径、弦管轴向应力对TX型圆管节点轴向承载力的影响，以及弦管长度和边界条件对TT型圆管节点轴向承载力的影响。

刚性结构通常采用“Rayleigh法”的线性化方法近似计算结构的基频，但是单层索网体系属于非线性预应力体系，其自振频率会随着振幅发生变化。通过分析结果表明，当节点质量较大时，用假定惯性荷载的方法计算的误差较大；“Ray leigh 法”计算索网频率是基于微幅振动的假定，不能反映其振幅较大时的自振特性。本文采用连续化理论，推导了单层索网体系第一、二阶非线性自振频率近似公式，并将计算结果和瞬态分析结果进行对比，两者吻合较好。非线性自振特性的研究对于单层索网体系在风荷载作用下的响应分析具有十分重要的意义。

钢-混凝土组合扁梁是将钢梁内嵌于混凝土之中的新型组合梁，它能最大限度地降低结构的高度，形成类似“无梁楼盖”的结构体系，已在住宅钢结构中推广应用，其承载性能和设计方法研究引起了结构工程界的关注，本文采用通用有限元程序ANSYS研究了组合扁梁的承载力问题，通过建模计算了简支组合扁梁、悬臂组合扁梁和框架组合扁梁的承载力和变形特征，得到了相应的荷载2位移过程曲线，并与组合扁梁的试验结果进行了比较，验证了计算结果的正确性。