Coupled longitudinal and transverse vibrations of tensioned Euler-Bernoulli beams with general linear boundary conditions

The paper concerns coupling between longitudinal and transverse vibrations of tensioned Euler-Bernoulli beams with general linear boundary conditions of arbitrary elastic stiffness. The beams are assumed to be perfectly straight with symmetric boundary conditions, and excitation aligned with the longitudinal axis. Two types of excitation, harmonic and impact, are considered. A relatively simple approach is proposed to predict and qualitatively describe the coupling, allowing approximate explicit analytical expressions for the key parameters affecting the phenomenon. The beam model considered, with both ends supported by longitudinal, translational and rotational springs, can be used in particular to model tensioned bolts used in engineering. The effects of beam tension on the coupling phenomenon are revealed. A series of physical experiments is carried out to illustrate application of the obtained theoretical predictions. Numerical solution of the full nonlinear equations governing coupled transverse-longitudinal vibrations has been conducted to validate the theoretical predictions.