加劲外伸端板连接的弯矩-转角性能分析

提出新的理论模型,用于评估加劲外伸钢梁-柱端板连接的弯矩-转角(M)关系。根据对端板连接转动的定义,将端板连接分解为多个组成部分,包括面板区、螺钉、端板和柱翼缘。并对各个组成部分完整的加载-变形过程进行了分析。最后通过整合各个部分的反应得出整个连接件的加载-变形过程。此外,通过5个节点试验验证这个分析模型。对计算与试验结果比较可以得出,该分析模型可以准确评估端板连接的转动能力、弯矩-转角曲线和初始转动刚度。而且,它还可以分析对节点转动变形起作用的其他因素,如面板区的剪切变形、螺钉的拉长、端板和柱翼缘的弯曲变形等。该分析模型同时提供弯矩-剪切转角(Ms)和弯矩-缝隙转角(Mcp)曲线,这些曲线为详细分析端板连接的转动性能提供了可靠的基础。     

钢框架外伸端板连接节点计算方法探讨

由国内外研究成果发现多层钢框架连接节点多处在完全刚性和理想铰接这两种极端情况之间,而我国多层钢框架结构中已开始采用半刚性但是规范尚无相关规定。针对此介绍了半刚性连接的特性和国内外对此类节点提出了标准的构造建议,并对此类端板连接提出了相应的弯矩-转角(M-)曲线形式及简化计算方法,为我国钢结构设计规范关于半刚性端板连接的设计计算方法提供了有益补充。     

门式刚架端板连接节点弯矩-转角曲线计算模型

进行了8个门式刚架端板连接节点的有限元分析,得出节点构造形式、端板厚度等因素对节点受力性能的影响规律.提出了门式刚架端板连接节点的弯矩-转角曲线计算模型.该模型考虑了节点域斜向加劲肋的作用,也考虑了节点域局部屈曲的发展过程和节点组件间的相互作用.通过与有限元分析及试验数据对比,表明该模型能够很好地反映门式刚架端板连接节点的受力性能,初始刚度和极限承载力等关键指标吻合较好.     

高强螺栓端板连接节点的弯矩-转角关系研究

介绍了三种半刚性连接弯矩-转角关系曲线数学表达式，阐明了实用的三折线表达式用以描述高强螺栓端板连接的弯矩-转角关系，通过对比分析证明了该三折线表达式做出的曲线可以比较准确地预测高强螺栓端板连接节点的弯矩-转角变化趋势，为相关节点设计提供了有益参考。     

钢结构半刚性端板连接的设计方法与应用

针对我国多层钢框架结构中已开始采用半刚性节点而规范尚无相关规定的现状 ,介绍了半刚性连接的特性和国外常用半刚性端板连接的设计方法 ,分析总结了目前半刚性连接的研究和应用中存在的问题     

RCS梁柱节点半刚性连接弯矩-转角关系模型研究

梁柱节点作为RCS结构中的重要组成部分,其受力情况较为复杂,在地震作用下容易发生损伤。通过对RCS梁柱组合件抗震性能试验研究发现,该种梁柱节点连接并非是理想的刚性连接,而是一种半刚性连接。为了明确该种半刚性连接的受力及转动特性,系统探讨了柱面钢板厚度,钢梁高度、翼缘宽厚比、柱混凝土强度和楼板厚度等构造措施参数对该种半刚性连接在循环荷载下抗弯承载力以及初始转动刚度的影响。同时,基于参数分析和灵敏度计算结果,提出描述该种半刚性连接的弯矩-转角关系四折线模型。该模型计算结果与试验结果吻合较好,可以为基于半刚性连接的RCS组合结构设计提供参考。     

梁柱半刚性端板连接节点受力性能分析

对外伸高强螺栓端板连接节点的受力特性进行了分析，介绍了初始连接刚度的计算。通过分析，认为初始刚度与节点的构造有关，尤其是与连接件的抗弯刚度、板厚、以及螺栓的间距影响有关。     

半刚性端板连接的有限元模拟

所有的钢结构连接,是介于刚接和理想铰接之间的一种连接.而端板连接是一种典型的半刚性连接.通过对端板连接的有限元模拟,研究端板厚度等因素对节点性能的影响,为设计的合理性提供一些参考.     

外伸端板半刚性连接的初始刚度研究

钢结构中的梁柱节点并不是完全刚接或者完全铰接,而是属于半刚性连接.针对外伸端板半刚性连接,利用组件法推导其初始刚度的预测计算公式,并利用已有的试验数据验证其正确性,为实际工程中的应用奠定了理论基础.     

梁柱端板连接节点的初始转动刚度计算模型

首先利用分解法建立了梁柱螺栓端板连接节点的力学模型 ,然后基于梁板理论给出了节点初始转动刚度的解析公式。公式综合考虑了端板变形、柱翼缘以及螺栓对初始转动刚度的贡献 ,可方便地推广于平端板和外伸加劲端板连接初始转动刚度的计算。公式计算结果和试验结果以及有限元分析结果作了对比 ,吻合较好。同时给出了便于工程设计的简化公式。     

Development of moment-rotation model equations for flush end-plate connections

This paper presents the development of Ramberg-Osgood and Three-Parameter Power model prediction equations for the moment-rotation (M-θ) behavior of flush end-plate connections with one row of bolts below tension and compression flanges. A finite element model (FEM) of the connection region along with the connected beam and column is developed for load deformation analyses, which included material, geometric, and contact nonlinearities. The FEM model was verified with test results conducted and reported for flush end-plate connections in the literature during the 1980s. A matrix of test cases was obtained by varying the geometric variables of flush end-plate connections within their practical ranges. The connection M-θ data for these test cases were obtained by FEM analyses, which were then curve fitted to Ramberg-Osgood and Three-Parameter Power model equations to obtain parameters defining these equations. Finally, prediction equations were developed for parameters of the model equations as functions of geometric variables of the flush end-plate connections.     

A simplified analytical method for unbraced composite frames with semi-rigid connections

The original Muto’s method for the lateral force analysis of conventional unbraced bare steel frames is first modified to incorporate the effects of semi-rigid beam-to-column connections. From which, equations for the calculation of the inter-storey drifts of these frames are formulated using first principles. By comparing the frame analytical results calculated from a rigorous finite element programme, it is shown that the proposed method gives reasonably accurate internal forces and inter-storey drifts estimations of a sway bare steel frame with semi-rigid connections. The proposed modified Muto’s method is then further developed for the manual analysis of unbraced composite frame systems by introducing an improved equivalent beam stiffness to account for the variation of the beam stiffness in the hogging and sagging moment regions. The accuracy of this simplified analytical method is verified by the rigorous finite element analysis of an unbraced composite frame with semi-rigid connections. Last, a parametric study is conducted to quantify the effects of semi-rigid connections on the inter-storey drifts of unbraced composite frames under lateral loads.     

半刚性连接钢框架水平侧移的简化计算

以一榀半刚性钢框架模型为例,在某些假定条件下,导出了其在水平荷载作用下的弹性侧移公式,并与刚性钢框架在水平荷载作用下的侧移公式进行比较,引入框架梁名义线刚度的概念,提出了在半刚性钢框架设计中采用框架梁名义线刚度来考虑连接初始刚度对框架水平侧移的影响.     

Experimental and theoretical analysis of the moment-rotation behaviour of stiffened extended end-plate connections

A new theoretical model to evaluate the moment-rotation (M-?) relationship 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 () curves, which establish a reliable foundation for analysing the detailed rotational behaviour of end-plate connections.     

浅谈半刚性端板连接的撬力研究

对钢结构半刚性端板连接——外伸端板高强螺栓节点连接的计算方法进行了探讨,重点介绍了目前国内外对端板连接中关于撬力影响的研究情况,了解了外伸端板螺栓连接设计的一种实用计算方法。     

A simplified calculation method for gust factors

The gust-factor analysis of Greenway is reviewed and empirical formulae are proposed to replace two tabulated functions in the analytical prediction of the probability distribution for the largest short-time-averaged gust in a specified observation period. The resulting method is suitable for rapid use with a hand calculator.     

New moment-rotation equation for welded steel beam-to-column connections

A three-parameter tangent inverse equation is generically proposed for the non-linear moment-rotation (M-θ) relationship of semi-rigid steel beam-to-column connections. The parameters are the initial stiffness, the plastic stiffness, and a reference moment. Two commonly used welded moment connections are picked up for moment-rotation calculation and comparison between the results of the proposed model and those of a detailed nonlinear finite elements modeling. Semi-analytical equations are proposed for calculating the parameters containing basic factors affecting behavior of the connections. The coefficients of the equations are computed based on a data bank developed in this study using the finite element method. A large number of finite elements models covering the whole range of common dimensions of the above connections are analyzed. Accuracy of the finite element model is verified on the basis of the available test results from previous studies. Tensile tests for determination of material properties of weld to be used in the modeling are conducted. Comparison between the results of the semi-analytical equations and the finite element models shows that the proposed model is able to estimate the moment-rotation curves of the welded beam-to-column connections with very good accuracy.     

Bolted end-plate connections for steel structures

Obvious economies in practice have increased the popularity of these connections for steel framed buildings, but their actual behaviour in use is still debated. Extensive research in Denmark points to the hitherto undervalued significance of prying forces and suggests a more realistic design approach than the semiempirical basis of the current AISC Manual of Steel Construction.     

高层空间半刚性连接钢框架分析的QR法

采用双向三次B样条基函数及正交多项式乘积的线性组合,构造了空间钢框架结构分析QR法的整体位移函数,借助于有限元法的离散网格、单元刚度方程,通过单元结点位移和QR法广义位移的变换,建立起QR法的计算格式.基于半刚性连接钢框架结构的基本假定,在单元的刚度矩阵和等效荷载向量中引入无量纲刚度因子,通过刚度因子的不同取值,不但可以分析空间刚接框架、简支框架,还可以分析任意的半刚性连接钢框架.程序计算的结果证明了该算法的正确性及精确性.     

超大承载力端板连接节点有限元分析和设计方法

超大承载力端板连接节点能够提供比普通构造的端板连接节点和大承载力端板连接节点更大的抗弯承载力,可以应用于大跨或重载钢结构中。由于超大承载力端板连接节点的螺栓拉力分布不均匀、端板受力状态复杂,现有的端板连接节点设计方法不能直接应用。此文建立超大承载力端板连接节点的有限元模型,通过已有试验验证模型的可靠性|利用有限元模型分析单调荷载下超大承载力端板连接节点的受力性能,提出弯矩作用下受拉区端板的屈服线模型和受拉区螺栓承担拉力的分布模型。在所提模型的基础上基于我国规范提出超大承载力端板连接节点的抗弯承载力设计方法。比较所提设计方法得到的节点抗弯承载力设计值与有限元得到的屈服承载力,在我国规范规定的高强度螺栓受拉极限状态条件下所提方法得到的设计结果偏于安全。