On triply coupled vibrations of axially loaded thin-walled composite beams

摘要

Free vibration of axially loaded thin-walled composite beams with arbitrary lay-ups is presented. This model is based on the classical lamination theory, and accounts for all the structural coupling coming from material anisotropy. Equations of motion for flexural-torsional coupled vibration are derived from the Hamilton's principle. The resulting coupling is referred to as triply coupled vibrations. A displacement-based one-dimensional finite element model is developed to solve the problem. Numerical results are obtained for thin-walled composite beams to investigate the effects of axial force, fiber orientation and modulus ratio on the natural frequencies, load-frequency interaction curves and corresponding vibration mode shapes.