An investigation of stress wave propagation in a shear deformable nanobeam based on modified couple stress theory

Abstract

This paper presents a new investigation for propagation of stress wave in a nanobeam based on modified couple stress theory. Using Euler– Bernoulli beam theory, Timoshenko beam theory, and Reddy beam theory, the effect of shear deformation is investigated. This nonclassical model contains a material length scale parameter to capture the size effect and the Poisson effect is incorporated in the current model.<br><br>Governing equations of motion are obtained by Hamilton’s principle and solved explicitly. This solution leads to obtain two phase velocities for shear deformable beams in different directions. Effects of shear<br><br>deformation, material length scale parameter, and Poisson’s ratio on the behavior of these phase velocities are investigated and discussed.<br><br>The results also show a dual behavior for phase velocities against Poisson’s ratio.