Study On The Dynamic Post-buckling Performance Of The SPS Hatch Cover Structure Based On Progressive Failure Method

SPS sandwich plate has the characteristics of light weight,high specific strength,high specific stiffness,corrosion resistance and so on.It is widely used in aerospace,ship,bridge and other fields and is widely concerned by domestic and foreign scholars and industry experts.SPS sandwich plate buckling critical load of analytical solution is established based on the theory method.This paper studies the failure mode and the progressive failure analysis methods of SPS sandwich plate by using experimental method and analyzes the dynamic post-buckling equilibrium path.The buckling and dynamic post-buckling performance of SPS hatch is studied through this way and ultimate strength can been obtained.The main research contents are as follows:(1)Based on the laminated plates and sandwich plate theory,the Zig-zag mathematical model is used for SPS sandwich plate.The first-order shear deformation theory is used for face sheet and the Reddy higher-order shear deformation theory is used for the core.The buckling critical loads of SPS sandwich plate are solutioned by program and ANSYS,which are compared with existing results to verify the correctness of the finite element simulation,The geometric parameters of the SPS sandwich plate and the influence of material parameters on its stability are studied;(2)The mechanical properties of the lab-made SPS sandwich plate are tested,and the elastic modulus,poisson’s ratio and yield strength of the core material polyurethane elastomer are obtained.The interlayer shear strength of SPS sandwich plate is obtained by layer shear test.The side pressure test of SPS sandwich plate is carried out,and the failure mode and load displacement curve of sandwich plate are obtained;(3)Using ANSYS Upfs to generate SPS user-defined version of sandwich plate failure criteria,and progressive failure analysis based on APDL language subroutine,including failure criteria,failure element stiffness degradation and failure criterion,etc.,which can realize failure initiation of SPS sandwich plate.It is concluded that the failure mechanism of sandwich plate and the ultimate failure load,and compared with the experimental results to verify the accuracy of subprogram;The dynamic post-buckling analysis of typical structure of SPS hatch cover is carried out,and the influence of geometric parameters on the post-buckling of the structure is studied and discussed;(4)With the traditional steel hatch cover as the alternative target,three design schemes of SPS hatch cover are proposed based on the principle of equivalent design.Based on the static strength calculation and analysis,the optimal scheme is preliminarily determined,and the stability of the optimal scheme is parameterized for discussion.The structural parameters are optimized with the goal of weight reduction,and the lightweight design scheme of SPS hatch cover structure is obtained.The dynamic post-buckling analysis of lightweight design scheme for SPS hatch covers is carried out,the progressive failure process of the hatch covers is discussed in detail,and the influence of boundary conditions and combined loads on the post-buckling performance of SPS hatch covers is studied.