Theoretical Derivation And Engineering Design On Corrugated Sandwich Panels Under Bending Loads

As a new type of multi-function composite sandwich structure, corrugated sandwich panels are widely used in the field of engineering structural design as lightweight, high toughness, good impact resistance and so on. A typical corrugated sandwich panel is composed of two face sheets and corrugated core layer which between the two face sheets, and combined the two face sheets and corrugated core layer as a whole by welding or cementing, the corrugated core layer separated the two face sheets and have ability to resist the deformation in the vertical direction. Reasonable design of the structure will affect the static and dynamic mechanical properties of the whole corrugated sandwich panel; however, the numerical analysis method based on finite element will result in long calculation time, the experimental research analysis method will affect the accuracy of the results due to the defects occur in the specimen manufacturing process, and the large-scale structure will be limited by the laboratory equipment. Therefore, the thesis intends to investigate the performance of aluminous corrugated core sandwich panel under bending loads by using theoretical derivation, and conduct the structural and material parameters’ anti-bending design.The thesis derived the equivalent material parameters of the corrugated core layer, which could considered as an orthotropic panel, by using energy method and equivalent homogeneous model, and combined the corrugated core layer and two panels together to obtain the equivalent material parameters of the whole structure through the classical laminate theory. And these equivalent material parameters were comparing with finite element solutions. The corrugated sandwich panel was considered as orthotropic panel by equivalent method, and then through the Mindlin orthotropic plate theory, the thesis obtained the closed-form solutions of the displacement for corrugated sandwich panel under bending loads in specified boundary conditions. And the finite element solutions obtained by finite element method are compared with the closed-form solutions and studied the influence of micro-structure parameters on central point maximum displacement of corrugated sandwich panel under bending load at the same time. Finally, based on the derived analytical solutions of displacement, the multi-objective optimization design of micro-structure parameters for corrugated sandwich panel under bending load was conducted, which the optimization targets are minimize the displacement and minimize the total mass, and obtain the Pareto frontier contains a set of optimal targets by NSGA-II. Based on the derived analytical solutions of displacement, the anti-bending design of macro-structure parameters and the choice of material were conducted.In this thesis, theoretical derivation and anti-bending properties of corrugated sandwich panels have been studied, provided some technical support for the application of corrugated sandwich panels under certain conditions, and the results of the thesis have certain guiding significance and reference value for parameters selection and material selection of corrugated sandwich panels in the structural design.