Milad Nazarzadeh - Mechanical Engineering Department, Tabriz University
Hasan Biglari - Mechanical Engineering Department, Tabriz University
Vahid Jahangiri - Mechanical Engineering Department, Tabriz University

In this paper, the effect of Poisson’s ratio and rotary inertia on the free vibration of laminated composite beam based on Euler-Bernoulli, Timoshenko and Third order theories has been studied. The investigation of free vibration of laminated beams based on high-order theories includ-ing Poisson’s effects and rotary inertia is presented in this paper for the first time. Equations of mo-tion have been extracted by Hamilton’s principle. Differential equations of motion solved an-alytically and natural frequencies of beam with different boundary conditions had been ex-tracted. Results compared with some available analytical solutions obtained by other corre-sponded author in the literature. Effect of rotary inertia, Poisson’s ratio, fiber orientation and thickness on the free vibration of laminated composite beam and also investigated.

Poisson’s ratio; rotary inertia; laminated composite beam; natural frequency