Compressive bucking and post-bucking mechanical properties of aeronautic composite stiffened panel

Abstract

Aeronautical composite stiffened panels are widely used in aeronautical structure design because of their good mechanical properties. In this paper，the compressive buckling and post-buckling mechanical properties of aeronautical composite stiffened panels were studied. Firstly，the compressive stability of composite stiffened panels was calculated by engineering method，and the predictions of the buckling and failure loads of stiffened panels were obtained；Secondly，the compression stability experiment of the composite stiffened plate is carried out，and the buckling and failure modes，the load-strain and load displacement relationship of the experimental piece，and the buckling and failure loads of the experimental piece are obtained. The results show that the calculated results by engineering method are in good agreement with the test results，and the error of buckling load and failure load are 6.12% and 9.31% respectively. The reasonable application of engineering method can provide better guidance for the experiment；The failure modes of stiffened panels are the delamination of the panels，the bulging and tearing of the skin，the fracture of the stiffeners and the debonding of the stiffeners-panels. The buckling ratio of composite stiffened plates is 1.65，the composite stiffened plates have strong post-buckling bearing capacity；The post-buckling bearing capacity of stiffened plates can be fully applied in engineering to improve the utilization efficiency of structures.

Keywords

• composite material
• stiffened panel
• compress
• buckling
• post-buckling