Free vibrational analysis of composite beams reinforced with randomly aligned and oriented carbon nanotubes, resting on an elastic foundation

Abstract

The main interest of this paperwork is to examinate the dynamic behavior (free vibrational response) of carbon nanotubes (CNT) composite beams standing on an elastic foundation of Winkler-Pasternak’s. The affected beam consists of a polymer matrix reinforced with single-wall carbon nanotubes (SWCNT’s), in which, a large number of CNT’s reinforcement of infinite length are distributed in a linear elastic polymer matrix. In this study the CNT’s are considered either aligned or randomly oriented on the matrix.
 A refined high-order beam theory (RBT) is adopted in the present analysis using a new shape function. The refined beam theory which is summarized by differentiating the displacement along the beam transverse section into shear and bending components, initially the material properties of the composite beam (CNTRC) are estimated using the Mori-Tanaka’s method. The beam is considered simply supported on the edge-lines. NAVIER’s solutions are proposed to solve the boundary conditions problems. Since there are no results to compare with in the literature; the results in this study are compared with a free vibrational analysis of an isotropic beam.  Several aspects such as the length/thickness ratio, volume fraction of nanotubes, and vibrational modes are carried out in the parametric study.