Higher-order beam theory for static and vibration analysis of composite thin-walled box beam

A higher-order beam theory suitable for accurate analysis of composite thin-walled box beams is developed. Because anisotropic and laminate effects in composite beams produce deformation patterns that do not appear in isotropic beams, accurate analyses for composite beams require elaborately defined sectional shape functions that describe local cross-sectional deformations. Here, we present a new systematic method to define these functions and establish a one-dimensional finite element based on a higher-order beam theory for composite thin-walled box beams. The validity of the developed approach is checked by solving static and eigenvalue problems with composite thin-walled box beams, and by comparing the obtained numerical results with those obtained by ABAQUS shell elements.