Non-linear stability and load-carrying capacity of thin-walled laminated columns in aspects of coupled buckling and coupled stiffness submatrix

Abstract

To assess a load-carrying capacity of compressed thin-walled plate structures in the paper the coupling buckling phenomenon of compressed columns was analyzed. The columns were of open cross-sections and made of coupled laminate. Selected configuration of laminate layers enables different types of coupling between membrane and bending states which describes the coupling stiffness submatrix B. Element values of stiffness matrix ABD were determined with application of classical laminate plate theory CLPT.The main aim of the work is to estimate an influence of chosen submatrix B elements on buckling, postbuckling and load-carrying capacity of analyzed thin-walled structures. The problem was solved with the Koiter’s theory application. The detailed computations were performed for uniformly compressed lip channel and top hat channel. The dimensions of both columns were chosen in a way which allowed to observe the strong coupling effect among different buckling modes. It were two laminate configurations considered which differed in value of stiffness reduction coefficients.