Abstract
This Note proposes an extension to composite section of the non-uniform (out-of-plane) warping beam theory recently established for homogeneous and isotropic beam by R El Fatmi (C R. Mecanique 335 (2007) 467-474) For the present work which constitutes a first step of this extension the cross-section is assumed to be symmetric and made by orthotropic materials however Poisson s effects (called here in-plane warping) are also taken into account Closed form results are given for the structural behavior of the composite beam and for the expressions of the 3D stresses these ones easy to compare with 3D Saint Venant stresses make clear the additional contribution of the new internal forces induced by the non-uniformity of the (In and out) warpings As first numerical applications results on torsion and shear-bending of a cantilever sandwich beam are presented (C) 2010 Academie des sciences Published by Elsevier Masson SAS All rights reserved