ABSTRACT
Based on both molecular mechanics and computational structural mechanics, a threedimensional
(3D) equivalent beam element is developed to model a C-C covalent bond
on carbon nanotubes (CNTs) whereas the van der Waals forces between atoms in the
different walls of multi-walled CNTs are described using a rod element. The buckling
characteristics of CNTs are conveniently analyzed by using the traditional finite element
method (FEM) of a 3D beam and rod model, termed as molecular structural mechanics
approach (MSMA). Moreover, to model the CNTs with large length or large diameter,
the validity of Euler's beam buckling theory and a shell model with proper properties
defined from the results of MSMA is investigated. The predicted results by this simple
continuum mechanics approach agree well with the reported experimental data.