A Nonlocal First Order Shear Deformation Theory for Vibration Analysis of Size Dependent Functionally Graded Nano beam with Attached Tip Mass: an Exact Solution

Journal of Solid Mechanics

مقاله 2، دوره 10، شماره 1، خرداد 2018، صفحه 23-37   

نوع مقاله: Research Paper

نویسندگان

M Ghadiri^* ؛ A Jafari

Faculty of Engineering, Department of Mechanics, Imam Khomeini International University, Qazvin, Iran

چکیده

In this article, transverse vibration of a cantilever nano- beam with functionally graded materials and carrying a concentrated mass at the free end is studied. Material properties of FG beam are supposed to vary through thickness direction of the constituents according to power-law distribution (P-FGM). The small scale effect is taken into consideration based on nonlocal elasticity theory of Eringen. The nonlocal equations of motion are derived based on Timoshenko beam theory in order to consider the effect of shear deformation and rotary inertia. Hamilton’s principle is applied to obtain the governing differential equation of motion and boundary conditions and they are solved applying analytical solution. The purpose is to study the effects of parameters such as tip mass, small scale, beam thickness, power-law exponent and slenderness on the natural frequencies of FG cantilever nano beam with a point mass at the free end. It is explicitly shown that the vibration behavior of a FG Nano beam is significantly influenced by these effects. The response of Timoshenko Nano beams obtained using an exact solution in a special case is compared with those obtained in the literature and is found to be in good agreement. Numerical results are presented to serve as benchmarks for future analyses of FGM cantilever Nano beams with tip mass.

کلیدواژه‌ها

Timoshenko Beam Theory؛ Free vibration؛ Functionally graded Nano beam؛ Nonlocal elasticity theory؛ Tip mass

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