This paper reports the most recent developments concerning Generalized Beam Theory (GBT) formulations, and corresponding finite element implementations, for steel-concrete composite beams. These formulations are able to perform the following types of analysis: (i) materially nonlinear analysis, to calculate the beam load-displacement response, up to collapse, including steel plasticity, concrete cracking/crushing and shear lag effects, (ii) bifurcation (linear stability) analysis, to obtain local/distortional bifurcation loads and buckling mode shapes of beams subjected to negative (hogging) bending, accounting for shear lag and concrete cracking effects and (iii) long-term service analysis including creep, cracking and arbitrary cross-section deformation (which includes shear lag) effects. The potential (computational efficiency and accuracy) of the proposed GBT-based finite elements is illustrated through several numerical examples. For comparison purposes, results obtained with standard finite strip and shell/brick finite element models are provided.

中文翻译：

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钢-混凝土组合梁的 GBT 分析：最新进展

本文报告了关于钢-混凝土复合梁的广义梁理论 (GBT) 公式和相应的有限元实施的最新进展。这些公式能够执行以下类型的分析：(i) 材料非线性分析，用于计算直到倒塌的梁载荷-位移响应，包括钢塑性、混凝土开裂/破碎和剪力滞效应，(ii) 分叉 (线性稳定性）分析，以获得承受负（拱形）弯曲的梁的局部/扭曲分叉载荷和屈曲模式形状，考虑剪力滞和混凝土开裂效应，以及（iii）长期服务分析，包括蠕变、开裂和任意交叉-截面变形（包括剪切滞后）效应。通过几个数值示例说明了所提出的基于 GBT 的有限元的潜力（计算效率和准确性）。出于比较目的，提供了使用标准有限条和壳/砖有限元模型获得的结果。