Analysis system of stability and strength for airframe composite stiffened plate/shell

With more and more wide application of composite materials as the main carrier structures of aircraft (for example airframes), theories and procedures of their speedy simulation and layout calculation as well as their stability (stiffness) and strength analysis are needed urgently in engineering. Based on the theory of stability and recent advances in research about composite stiffened plate/shells with arbitrary direction rib elements as well as the failure theories of laminated composite plate/shells, this article developed a new procedure for the stability and strength analysis (CSSAP) of airframe composite stiffened plate/shells. This analysis system can not only be used to analyze the linear stability and strength of composite plate/shells with ribs, but also their nonlinear stability and strength. Both the critical buckling strain and the stress in post buckling can also be obtained on a fairly coarse (not too fine) mesh scale. A comparison with the results of existing methods shows that this procedure can better satisfy the demands of precision in engineering. Moreover, according to the calculation results of a typical example of a real airframe, this procedure can be effectively used to analyze complex structures.