1School of Mechanical Engineering, College of engineering, University of Tehran, Tehran, Iran
2Department of Mechanical Engineering, Sharif University of Technology, Tehran, Iran
School of Mechanical Engineering, College of engineering, University of Tehran, Tehran, Iran
An analytical study using Variational Iteration Method (VIM) is carried out in order to investigate the vibrations of electro-statically actuated double-clamped and simply-supported micro-beams. Effects of applied voltage and residual axial load on the nonlinear natural frequency and deflection of the micro-beams are studied. It shows that pre-compression in micro-beams increases the amplitude of deflections for a specific applied voltage. Also, an increase in pre-tension motivates the micro-beam to show more nonlinear behavior in an applied voltage. Predicted results are compared with the experimental data available in the literature and also with numerical results which shows a good agreement. It is concluded that the second order approximation of the VIM leads to highly accurate solutions which are valid for a wide range of vibration amplitudes.