TY  - JOUR
T1  - Multiobjective Mechanical Buckling Optimization of Variable Thickness
FG Cylindrical Shell with Initial Imperfection
AU - Hayati, M. AU - Atai, A.A. 
JO  - Journal of Engineering and Applied Sciences
VL  - 14
IS  - 2
SP  - 658
EP  - 665
PY  - 2019
DA  - 2001/08/19
SN  - 1816-949x
DO  - jeasci.2019.658.665
UR  - https://makhillpublications.co/view-article.php?doi=jeasci.2019.658.665
KW  - FGM variable thickness
KW  -critical buckling load
KW  -initial geometric imperfections
KW  -optimization
KW  -multiobjectiveGenetic algorithm
KW  -cylindrical
AB  - In this study, we evaluate the buckling load with energy approach with finite element models for
mechanical buckling analysis of Functionally Graded Materials (FGMs) variable thickness cylindrical shell with
initial imperfection. By defining the shell, mathematical equations are obtained which are dominating on the
displacement of the shell, using third order shear deformation theory and Von Karman-type kinematic
nonlinearity relationships. Considering cylindrical shell properties, so that, the function of properties change
is considered as exponential function and variable properties are in the line with the thickness and variable
length, the research continues and by applying a mechanical force in the longitudinal direction of the shell,
strain-displacement relations and external load research in to the shell and bearing in mind the lasting
relationship, the nonlinear finite element model of the relationship of the cylindrical shell of FGM variable
thickness with initial imperfection will be defined. Using picard numerical iterative method, nonlinear finite
element model of the problem will be solved and then using the Budiansky’s criterion, critical buckling load is
achieved. Simultaneous with the critical buckling load, another objective should be minimized like weight and
cost of manufacturing cylindrical shell. Therefore, multi-objective optimization problem is defined in which
using the genetic algorithm method such goals can be achieved, namely, maximum critical buckling load and
minimum weight of the shell and are shown in Pareto Front diagram.
ER  -