Research on free vibration of axially functionally graded graphene platelet reinforced composite beams in thermal environment

This paper investigates the fundamental frequency analysis of Axially Functionally Graded Graphene Platelets Reinforced Composite (AFG-GPLRC) beams in thermal environments. The graphene platelets are dispersed in five different patterns (UD, AFG-X, O, A, V) along the axis, either uniformly or non-uniformly. The effective material properties are determined using an improved Halpin-Tsai micromechanical model and the Rule of mixture. The governing equation, derived from the Euler-Bernoulli beam theory, is solved using the weighted residue method (Galerkin's method) to obtain element matrices. The accuracy of the analysis is confirmed by comparing the results with existing solutions. A comprehensive parametric study is conducted to investigate the impact of distribution patterns, graphene content, geometric parameters, and temperature changes on the free vibration behaviour of AFG-GPLRC beams. Due to the low graphene content used, the thermal properties of AFG-GPLRC were not significantly affected, and a significant decrease in the fundamental natural frequency was observed when the beam underwent a temperature change. This effect was consistent regardless of the boundary condition and distribution pattern.