S.A Galehdari - Department of Mechanical Engineering, Najafabad Branch ,Islamic Azad University, Najafabad, Iran---- Modern Manufacturing Technologies Research Center, Najafabad Branch ,Islamic Azad University, Najafabad, Iran
A.H Hashemian - Mechanical and Aerospace Engineering Department, Science and Research Branch, Islamic Azad University ,Tehran, Iran
J.E Jam - Composite Material & Technology, Malek Ashtar University of Technology, Tehran, Iran
A Atrian - Department of Mechanical Engineering, Najafabad Branch ,Islamic Azad University, Najafabad, Iran---- Modern Manufacturing Technologies Research Center, Najafabad Branch ,Islamic Azad University, Najafabad, Iran

Buckling strength of composite latticed cylindrical shells is one of the important parameters for studying the failure of these structures. In this paper, new governing differential equations are derived for latticed cylindrical shells and their critical buckling axial loads. The nested structure under compressive axial buckling load was analyzed. Finite Element Method (FEM) was applied to model the structure in order to verify the analytical results. The obtained results were validated based upon the results of previous case studies in literature. For the squared type of lattice composite shells, a new formula for the buckling load was developed and its value was compared to the critical load, using FEM with 3D beam elements. The processes were carried out for three different materials of Carbon/Epoxy, Kevlar/Epoxy and EGlass/Epoxy.

Lattice structures, Composite materials, Finite Element Method, Buckling loading