http://www.scielo.br/scielo.php?script=sci_arttext&pid=S2448-167X2016000300273&lng=pt&nrm=iso
ABSTRACT The study of non-symmetrical composite columns is complex and European and North American standards only approach this issue superficially. In this text, a new proposal is presented for non-symmetrical composite column design subject to biaxial bending and axial compression, based on the compatibility of the deformation method, which considers the nonlinearity of the material with constitutive models according to Brazilian standards and geometric nonlinearity, as well as the equilibrium of the column in the displaced position. As a strategy for solving the general method, use is made of the "fiber element method", and for solving problems involving nonlinear equilibrium equations, the Newton-Raphson method.
http://www.scielo.br/scielo.php?script=sci_arttext&pid=S2448-167X2016000300273&lng=pt&nrm=iso