Analysis Of Open-hole And Reinforcement Composite Honeycomb Sandwich Panel With Progressive Damage In Postbuckling

Composite honeycomb sandwich panel,which is widely used in the area of aerospace,etc.,has the advantages of high specific strength,bigger stiffness,high stability and low cost and is easy to design.Currently,there is almost no scholar analysis on buckling and postbuckling with progressive damage for open-hole and reinforcement composite honeycomb sandwich panel.But in the real project,it is important to be able to know the change rule of postbuckling limit load for open-hole and reinforcement composite honeycomb sandwich panel under different conditions.In this paper,after the element stress is extracted,the step-by-step damage analysis is made by significantly reducing the elastic modulus of invalid unit based on the Hoffman principles and the principles of maximum shearing stress,and then the structure ultimate bearing capacity in postbuckling is obtained with the finite element software called Ansys and the computer program compiled by ADPL.In this article,at first,the postbuckling process of composite honeycomb sandwich borad simply supported on four edges happened under the axial compression and shear loading is simulated,and the impact on plate limit load and damage area by the change aspect ratio,proportion of honeycomb,hole diameter,hole location and open hole number is discussed.Second,the postbulkling damage process of the open-hole composite honeycomb sandwich plate under axial direction load and the shearing load when the inserted layer reinforcement and wrapped edge reinforcement are applied to open-hole composite honeycomb sandwich plate is also discussed in this article.At last,the limit load of the sandwich plate laid in the quasi-isotropic way and that of the sandwich plate laid in a symmetric way are compared.The results show that all the limit loads of the plates increase first and then decrease with the increase of θ under the compression load or shear load.With the overall thickness unchanged,both the increases for the hole diameter and the honeycomb thickness will make the bulking mode change from happening in overall area to local areas;the increasing of hole diameter,the thickness of honeycomb,the number of the holes and the offset will cause the decrease of the structural limit load;the ultimate bearing capacity will increase with the increase of reinforcement range;the effectiveness of inserted layer reinforcement becomes better under the axial compression load while the wrapped edge reinforcement limit bearing capacity increases greater under the shearing load.For the plate without holes under the axial load and the plate with two holes under the shearing load,the ultimate bearing capacity reaches the largest level when the plate is laid in an quasi-isotropic way[0°/90°/±45°/core]s,and the ultimate bearing capacity reaches the largest level when the plate is laid in an angular symmetric way for other working conditions.