Thin-walled curved box beam structures especially rectangular members are widely used in mechanical and architectural structures and other engineering fields because of their high strength-to-weight ratios. In this paper, we present experimental and theoretical analysis methods for the static analysis of thin-walled curved rectangular-box beams under in-plane bending based on 11 feature deformation modes. As to the numerical investigations, we explored the convergence and accuracy analysis by normal finite element analysis, higher-order assumed strain plane element, deep collocation method element, and inverse finite element method, respectively. The out-of-plane and in-plane characteristic deformation vector modes derived by the theoretical formula are superimposed by transforming the axial, tangential, and the normal deformation values into scalar tensile and compression amounts. A one-dimensional deformation experimental test theory is first proposed, formulating the specific contributions of various deformation modes. In this way, the magnitude and trend of the influence of each low-order deformation mode on the distortion and warping in the actual deformation are determined, and the significance of distortion and warping in the actual curved beams subjected to the in-plane loads is verified. This study strengthens the deformation theory of rectangular box-type thin-walled curved beams under in-plane bending, thus providing a reference for analyzing the mechanical properties of curved-beam structures.

中文翻译：

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平面弯曲下薄壁弯矩矩形箱形梁的理论与实验分析

薄壁弯曲箱形梁结构，尤其是矩形构件，由于其高的重量重量比而被广泛用于机械和建筑结构以及其他工程领域。本文提出了基于11种特征变形模式的薄壁弯曲矩形箱形梁平面内弯曲静力分析的实验和理论分析方法。对于数值研究，我们分别通过普通有限元分析，高阶假定应变平面单元，深搭配方法单元和逆有限元方法探索了收敛性和精度分析。将理论公式推导出的平面外和平面内特征变形矢量模式通过对轴向，切向，法向变形值分为标量拉伸和压缩量。首先提出了一维变形实验测试理论，阐述了各种变形模式的具体贡献。这样，确定了每个低阶变形模式对实际变形中的变形和翘曲的影响的大小和趋势，并且确定了在平面内载荷下实际弯曲梁中变形和翘曲的重要性。已验证。该研究加强了矩形箱形薄壁弯梁在面内弯曲下的变形理论，为分析弯梁结构的力学性能提供了参考。制定各种变形模式的具体贡献。这样，确定了每个低阶变形模式对实际变形中的变形和翘曲的影响的大小和趋势，并且确定了在平面内载荷下实际弯曲梁中变形和翘曲的重要性。已验证。该研究加强了矩形箱形薄壁弯梁在面内弯曲下的变形理论，为分析弯梁结构的力学性能提供了参考。制定各种变形模式的具体贡献。这样，确定了每个低阶变形模式对实际变形中的变形和翘曲的影响的大小和趋势，并且确定了在平面内载荷下实际弯曲梁中变形和翘曲的重要性。已验证。该研究加强了矩形箱形薄壁弯梁在面内弯曲下的变形理论，为分析弯梁结构的力学性能提供了参考。验证了平面弯曲载荷作用下实际弯曲梁的变形和翘曲的重要性。该研究加强了矩形箱形薄壁弯梁在面内弯曲下的变形理论，为分析弯梁结构的力学性能提供了参考。验证了平面弯曲载荷作用下实际弯曲梁的变形和翘曲的重要性。该研究加强了矩形箱形薄壁弯梁在面内弯曲下的变形理论，为分析弯梁结构的力学性能提供了参考。