Research On The Mechanical Characteristics Of Stiffened Plate Structures With Bending Radius

Based on the summary of the existing research results of domestic and foreign scholars and the specifications of various countries,this paper uses ANSYS finite element software to analyze the unidirectional uniform compression four-sided simply supported curved surface stiffener(including the convex curvature of the mother plane,the concave curvature of the plane and(In-plane bending stiffeners).In the field of bridge engineering,curved steel box girders,variable-height steel box girders and arch bridge steel box arch ribs have all widely used curved stiffeners.However,there is very little research on the mechanical properties of such curved stiffened plates at home and abroad,and the relevant national regulations are also lacking in relevant provisions.Therefore,the study of the mechanical characteristics of stiffened plates with bending radii has certain guiding significance for practical engineering.For curved stiffened plates with relatively large bending radii,since the bending radius has little effect on its bearing capacity,it can be calculated approximately according to the theoretical formula in the existing specifications.When the bending radius is relatively small,because the effect of the additional bending moment is too large,the stiffening plate bearing capacity is very different from the calculated value of the specification,so it is necessary to quantitatively analyze the curved stiffening plate more systematically.In this paper,the stiffening plate with bending radius in the steel box arch rib is selected as the research object,and the influence of the bending radius on the out-of-plane convex curvature,out-of-plane concave curvature and in-plane bending stiffening plate’s mechanical characteristics is investigated.In the case of,the effects of initial geometric defects,welding residual stress and the coupling effect of the two on their bearing capacity are discussed separately;by increasing the longitudinal stiffener stiffness or reducing the distance between the diaphragms,further discussion on improving longitudinal stiffener stiffness or When reducing the distance between the diaphragms,the reduction in the bearing capacity of the curved stiffener due to the bending radius can be eliminated.This paper introduces a bending radius reduction factor to modify the discrete "pressure bar" model,and derives a calculation formula suitable for the bearing capacity of stiffened plates with bending radius.Finally,this paper compares the finite element calculation results with the data of the experimental research on the steel box arch ribs in the existing literature.The results prove that the error between the experimental data and the calculation results in this paper is between 2.5% and 6.5%.It can be seen from the analysis that when the bending radius is greater than 220 m,the stress characteristics of the out-of-plane curved stiffeners are close to the linear stiffeners;increasing the stiffness of the longitudinal ribs or reducing the spacing of the diaphragms has a significant effect on its bearing capacity,but both With the increase of the bending radius,it showed a weakening trend.The bending radius and increasing the stiffness of the longitudinal ribs have almost no effect on the bearing capacity of out-of-plane concave stiffeners;reducing the spacing of the diaphragm has a greater effect on its bearing capacity,and will not decrease with the increase of the bending radius.The effect of bending radius on the bearing capacity of in-plane bending stiffeners is negligible;increasing the stiffness of longitudinal ribs and reducing the spacing of diaphragms have a significant effect on its bearing capacity.