Free Vibration and Buckling Analysis of Axially Loaded Double-Beam Systems with Generalized Boundary Conditions.

Double-beam systems have found many applications in civil and mechanical engineering. Extensive works of research have been conducted on the investigation of double-beam systems in which some have studied the vibration characteristics of general double-beam systems without considering the effect of axial load, whereas others investigated the vibration and buckling of axially loaded double-beam systems with classical boundary conditions. A few previous studies have considered a general axially loaded double-beam system, but none of them have provided a general solution to calculate the critical buckling load of the system with arbitrary boundary conditions. In the present study, free vibration and buckling of an axially loaded double-beam system, which was composed of two nonidentical beams with generalized boundary conditions, were analytically studied by using the Euler–Bernoulli beam theory. A semianalytical method was proposed to calculate the natural frequencies and mode shapes of the system, and an explicit formula was derived to determine the critical buckling load of the system. Parametric investigations were performed to study the influences of the connecting stiffness of the interlayer and axial loads on the dynamic characteristics and critical buckling load of the system. Results show that the proposed method can be used for free vibration and buckling analyses of generalized double-beam systems subjected to axial loads. [ABSTRACT FROM AUTHOR]