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This research deals with the evaluation of buckling behavior for 6061-T4 aluminum alloy under increasing compressive dynamic loads. Two types of columns, long, and the intermediate columns were used. The number of specimens used in the dynamic axial compression test were 9 samples .(1%) of the length column is the allowable lateral deflection. For the purpose of calculating the initial deflection, the digital dial gauge was used and the instrument was set at a distance of (0.7) of length from the fixed condition for the column. A control system is designed to evaluate the critical buckling and to prevent sample failure. The control system consists of a measuring circuit (transmitter circuit) with a flex sensor installed at 0.7 of the total column length of the column's fixed condition. In addition, the system contains a shutdown circuit (receiver circuit) to switch off the machine at critical load with a mobile phone for the purpose of displaying deflection data. The connection between the transmitter circuit and the receiver wirelessly through the RF sensor and between the transmitter circuit and mobile phone also wirelessly via Bluetooth. The results obtained were experimentally compared with the Perry-Robertson formula. It was found that the Perry-Robertson formula was a good agreement with the experimental results with a safety factor of (1.2) .

This paper present an investigation of the collapse load in cylinder shell under uniform external hydrostatic pressure with optimum design using finite element method via ANSYS software. Twenty cases are studied inclusive stiffeners in longitudinal and ring stiffeners. Buckling mode shape is evaluated. This paper studied the optimum design generated by ANSYS for thick cylinder with external hydrostatic pressure. The primary goal of this paper was to identify the improvement in the design of cylindrical shell under hydrostatic pressure with and without Stiffeners (longitudinal and ring) with incorporative technique of an optimization into ANSYS software. The design elements in this research was: critical load, design variable (thickness of shell (TH), stiffener’s width (B) and stiffener’s height (HF). The results obtained illustrated that the objective is minimized using technique of numerical optimization in ANSYS with optimum shell thickness and stiffener’s sizes. In all cases the design variables (thickness of shell) was thicker than the monocoque due to a shell’s thicker is essential to achieve the strength constraints. It can be concluded that cases (17,18,19, and 20) have more than 90% of un-stiffened critical load. The ring stiffeners causes increasing buckling load than un-stiffened and longitudinal stiffened cylinder.

Experimental work and finite element techniques were used to analyze the tensile and buckling characteristics of carburized low carbon steel columns for different diameters.The back of carburization consists of hardwood charcoal mixed with barium carbonate as the energizer. The specimens were carburized using (30%) of energizers at temperature equal to (900ºC) for 5 five hours.The modulus of elasticity as measured experimentally was used in FEM (ANSYS) to calculate the buckling load. The results of the study showed that the Vickers micro hardness increased from (HV=210) to (HV=525), the tensile strength increased from (708 MPa) to (1065 MPa) and critical buckling load increased from (18.37 kN) to (19.6 kN) for d=8mm. Also critical buckling load increased from (5.8 kN) to (19.2 kN) as the diameter of the carburized low carbon steel column increased from 6mm to 8mm respectively for FEA analysis.

The present work performs mechanical buckling analyses and experimental investigation on square plates with central cutout with (circular and elliptical) shape and with different size under uniaxial compressive loading, clamped from the loaded sides and free from others. The plates were mostly used in aircraft structures, rocket and automobiles is aluminum alloy (Al-2024 T3) because it has a high strength to weight ratio. The determination of critical buckling load of metallic plate is an important factor in determining the structural stability, which consider the best examination for buckling behavior. Experimental investigation was carried out on square plates by using strain gages. The experimental results for buckling load were compared with analytical results by using finite element structure analysis technique (F.E.M) i.e. using (ANSYS) software. Results have been presented that the square plates with circular and elliptical cutouts decrease in buckling strengths as the cutout sizes were increased. [ABSTRACT FROM AUTHOR]