Analysis of thin-walled curved box beam under in-plane flexure

A higher-order one-dimensional analysis of the in-plane flexural deformation of thin-walled curved box beams is carried out. The main contribution of the present work is to consider an additional degree of freedom accounting for the in-plane distortional deformation of the thin-walled cross section that is accompanied by the inplane bending deformation. Especially, we develop a systematic procedure to determine this bending distortion and formulate a higher-order beam theory including this additional degree of freedom. The significant contribution of the bending distortion to the beam flexibility is clearly demonstrated through several case studies.