Abstract A new numerical formulation includes the behavior of the semi-rigid connection into plastic-zone finite element model for steel plane frames. This Bernoulli-Euler formulation is an expansion and generalization of the slice technique with updated Lagrangian co-rotational system, presented before. Only one spring is placed in the finite element end node to allow the study of plasticity inside the member. The connection semi-flexibility factor eta controls this spring. It is defined for the beam length and can classify the connection as rigid or flexible. The eta effects on the vertical displacement function, the generality of the proposed model and the corresponding stiffness matrices are shown. The usage of another eta based on the finite element length is also explained. The advantages of semi-rigid connection behavior are discussed. Several answers were obtained, considering the connection stiffness and the inelastic behavior. This technique is applied to solve three benchmarked examples, applying connections of constant stiffness and semi-rigid curves from an existing data bank. The semi-rigid connection economy on beams, its appearing improvement of columns capacity, and the reduction of portal frame limit load justify this research. These examples are minimum requirements to develop the advanced direct analysis, which power is explored in the last one.

中文翻译：

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塑性区高级分析 – 包括半刚性连接的配方

摘要 一种新的数值公式将半刚性连接的行为纳入钢平面框架的塑性区有限元模型。这个 Bernoulli-Euler 公式是切片技术的扩展和推广，具有之前介绍的更新的拉格朗日共旋转系统。只有一个弹簧放置在有限元端节点中，以便研究构件内部的塑性。连接半柔度系数 eta 控制着这个弹簧。它是为梁长度定义的，可以将连接分为刚性连接或柔性连接。显示了对垂直位移函数的 eta 影响、所提出模型的一般性和相应的刚度矩阵。还解释了基于有限元长度的另一个 eta 的用法。讨论了半刚性连接行为的优点。考虑到连接刚度和非弹性行为，获得了几个答案。该技术应用于解决三个基准示例，应用来自现有数据库的恒定刚度和半刚性曲线的连接。梁上的半刚性连接经济性、柱承载力的显着提高以及门架极限荷载的减少证明了这项研究是合理的。这些示例是开发高级直接分析的最低要求，在最后一个示例中探讨了这种功能。柱容量的显着提高和门架极限载荷的减少证明了这项研究是合理的。这些示例是开发高级直接分析的最低要求，在最后一个示例中探讨了这种功能。柱容量的显着提高和门架极限载荷的减少证明了这项研究是合理的。这些示例是开发高级直接分析的最低要求，在最后一个示例中探讨了这种功能。