In this research, the proposed formulas determine the buckling coefficient as well as the local critical stress for I-shaped steel beams, accounting for the flange-web interaction when the flange-thickness to web-thickness ratio changes.

This paper is dedicated to the study of geometrically nonlinear behaviour of variable thickness functionallygraded plates subjected to uniaxial compressive forces. The plate’s geometry in this study could have either uniform thickness or symmetrical parabolic-form thickness.

An analytical approach for nonlinear buckling of functionally graded graphene platelet reinforced composite toroidal shell segments is presented in this paper. The Ritz energy procedure is executed, and radial pressure– deflection expression is constituted to obtain the postbuckling strength and critical buckling pressure of the shells.

In this paper, the nonlinear buckling behavior of functionally graded material (FGM) plates subjected to an axial compression is analytically investigated. Assuming that the plates are stiffened by FGM rectangular, I- and T-stiffeners.

The nonlinear buckling behavior of functionally graded graphene platelet reinforced composite (FG-GPLRC) cylindrical shells reinforced by ring, stringer and/or spiral FG-GPLRC stiffeners under torsional loads is studied by an analytical approach.

Buckling and postbuckling behaviors of porous functionally graded graphene platelets-reinforced composite (porous FG-GPLRC) cylindrical shells with stiffeners subjected to external pressures are presented in this paper. Three distribution types of porosity in the shells are considered. The smeared technique for stiffeners is employed to model the mechanical behaviors of the stiffened shells.

The nonlinear dynamic buckling responses of functionally graded graphene platelet reinforced composite (FG-GPLRC) cylindrical and sinusoid panels with porous core are presented in this paper. The governing formulations are established by applying the nonlinear higher-order shear deformation theory (HSDT).

The linear buckling behavior of functionally graded cylindrical shells with porous core stiffened by spiral stiffeners under axial compression using the first-order shear deformation theory is presented in this paper.

Objectives of the thesis: The literature review on the behaviours of composite beams shows that Ritz method is efficient to analyse the behaviours of composite beams with various boundary conditions, however, the number of researches used this method is still limited.

Study objectives: Determine the static buckling of the three-phase composite plates under the impact of mechanical loads. Determine the dynamic buckling of three-phase composite panel under the impact of hydrodynamic load.

This study has investi-gated the hollows considering the variable of its profile size, length and thickness. The boundary condition used the free-fixed configuration to convince the critical loads occurred from axial compression.

This paper deals with the elastica and buckling loads of the nonlinear elastic tapered cantilever columns subjected to an axial load at the free end. The column cross section is rectangular, where the width and depth vary linearly with the column axis.

In this paper, buckling behavior of aluminum cylindrical shell with rectangular cutout, subjected to axial pressure was studied by means of finite element simulations. The effects of geometric parameters (R, t, a, b and L) on the first buckling mode capacity of the shell were studied.

In this study, the behavior of two buildings designed with steel structures Buckling Restrained Braced (BRB) and conventional bending frame was studied to analyze their strengths against progressive collapse. The structures were designed and analyzed in accordance with Iranian regulation No. 2800 for the design of buildings.