عنوان مقاله [English]
نویسندگان [English]چکیده [English]
Buckling phenomena in different loading conditions, will lead to structural instability. Critical buckling load is dependent to factors such as geometry, size, load type, and boundary conditions. The aim of this paper is to study of the structure effect on the buckling behavior of carbon nanotubes (CNTs). In order to investigate the effect of chiral angle independent from size effects, all structures are used with the same dimensions but different chiralities. To simulate the chemical bonds between carbon atoms, carbon-carbon covalent bond energy is modeled using molecular mechanics theory and beam element. Coordinates of the nodes are determined using a simple algorithm. Then, chirality effect on axial and torsional buckling load is analyzed using finite element method for different structures. The results of this research show that the chiral angle has no significant effect on critical axial buckling load. However, CNT's structure has considerable influence on the stability. Chiral structures can be weaker or stronger against torsional buckling than symmetric structures.
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