Abstract: A series of warping shape functions is derived according to the successive corrective concept of warping based on the first warping theory, by which a high order warping theory for torsional analysis of composite thin walled beams with single cell closed section of arbitrary shape is prsented. The high order theory is an extention to the model of the warping displacement deployed by the first order theory.The influence of layering condition on the warping is also considered in the paper. The numerical results show that the convergence of this high order warping theory is quite good, and the result of the warping displacement distribution along the contour has better shown the geometrical characteristic of the cross section.

Key words: composites, thin-walled structure, high-or der warping theor y, layer ing, war ping displacement