Theoretical and experimental study on strain distribution of curved beam in-plane force considering pre-bending

Curved beam structures have been widely used in mechanical and architectural structures and other fields because of their high strength-to-weight ratio. This paper considers the strain distribution of a welded curved beam structure under the in-plane force pre-bending. First, a constitutive relationship is obtained based on tensile test of wall of the curved beam structure. Second, the strain distribution of the pre-bending curved plate is theoretically analyzed and experimentally verified as the initial strain. Subsequently, the theoretical and experimental strain distribution under the action of plane load is applied to the plane curved beam by solid mechanics, finite element, higher-order plane element, and experimental verification analysis. Third, a mathematical expression of strain on the upper and lower plates of the curved beam structure and curved plates on both sides, considering the pre-bending action under in-plane load, is established. Fourth, we establish the residual stress model of curved beam structure under welding action and analyze the strain distribution under the welding action on the section. Finally, we obtain the strain distribution of the curved beam structure under the influence of the curvature change. This study provides a theoretical- and engineering-based approach for analyzing the mechanical properties of curved beam structures.