▎ 摘 要
In this paper, a fully nonlinear spring-based structural mechanics approach, incorporating the modified Morse potential, is presented. Defects are defined as holes developed due to atom vacancies, as opposed to the perfect nanostructure of a graphene sheet. Appropriate boundary conditions are applied to evaluate the proposed method, under tensile and shear loadings, using finite element analysis. Material properties like stress-strain curves and elastic and fracture related properties of both pristine and defective graphene sheets, are predicted. The effect of defect size on mechanical response of the graphene with respect to its zigzag and armchair directions is explored. Analytical expressions of mechanical properties are obtained, using regression analysis of numerical results. The proposed method is validated by comparing predicted properties to data obtained from the literature. (C) 2011 Elsevier Ltd. All rights reserved.