The effect of the type of elements used to stiffen thin-walled skins of load-bearing aircraft structures on their operating properties. Experimental tests and numerical analysis

The paper presents results of a study on thin-walled structures modelling representative fragments of aircraft fuselages subjected to bending and torsion. The type of the considered load and deformation corresponds to the state of such structures under in-flight conditions. The subject of the study were structures made of composite materials. Adopted assumptions include admissibility of post-buckling deformation in the operating load regime. Results of experimental studies are presented together with nonlinear numerical analyses carried out with the use of the finite elements method applied to a number of variant structures provided with various types of skin stiffening elements. Operating properties of the examined structures have been compared on the grounds of adopted criteria.