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Aluminum alloys have found increasing use in space structures, mainly because of their high strength-to-weight ratio and satisfactory corrosion resistance. The work presented in this article is focused on finite element simulation of the failure behavior of aluminum alloy members subjected to an axial compression load and failing in overall buckling mode. The column members were fabricated by extrusion using the relatively new heat-treated aluminum alloy 6082-T6. An accurate finite element model has been developed for the simulation of aluminum alloy columns. The developed finite element model was verified against experimental results and demonstrated that it is capable of accurately predicting the deformed shapes and the ultimate loads of the tested columns. A parametric study was carried out on the stability of aluminum alloy column members failing by overall buckling. A fitting column curve was proposed for aluminum alloy design; it was somewhat more conservative than the column curve from current Chinese code GB50429. [ABSTRACT FROM AUTHOR]

6082 is a relatively new alloy that currently provides the best combination of properties in 6xxx series alloys. A series of tests was conducted on the stability of heat-treated aluminium alloy 6082-T6 circular tube columns to check the reliability of buckling strength predictions of 6082-T6 alloy circular tube columns using current design rules. First, nine stub columns were tested to obtain stress–strain curves and three parameters of the Ramberg–Osgood expression ( E , σ 0.2 and n ). The experimental stress–strain curves were in good agreement with the Ramberg–Osgood expression, and the mean value of σ 0.2 / n obtained from the tests was close to the Steinhardt assumption. Second, prior to column tests, the initial out-of-straightness of 15 circular tubes was accurately measured. Third, these 15 tubes, with five nominal slenderness ratios varying from 20.4 to 69.6, were tested between two pinned ends under axial compression to obtain failing modes and buckling strengths. Finally, the experimental buckling strengths were compared with the buckling strengths predicted by several current aluminium structure design codes, including the American Aluminium Design Manual (AA), Australian/New Zealand Standard 1664 (AS/NZS), and Eurocode 9 (EC9), as well as the general column curve formulation proposed by Rasmussen and Rondal [13] . These comparisons shows that the AA predictions are too conservative at small slenderness ratios, the AS/NZS predictions are unsafe at large slenderness ratios, the EC9 predictions are conservative, and the Rasmussen–Rondal formulation provides the closest and generally conservative strength predictions. [ABSTRACT FROM AUTHOR]

This paper presents a column curve formula capable of producing accurate strengths for extruded members of 6082-T6 aluminium-alloys failing by flexural buckling under axial compression. The formula uses the Perry-type curve. The material properties are expressed in terms of the Ramberg–Osgood parameters ( E , f 0.2 , and n ), obtained from tensile coupon tests of the finished product. 30 specimens of 6082-T6 aluminium alloy, including 15 H-section and 15 rectangular hollow-sections were tested under axial load using a pin-ended condition. Numerical models were then developed using the FE software ANSYS, and were verified against the experimental results. The coefficient of stability was determined and compared with the coefficients of stability from different codes such as American standard (American specification for aluminium structures), Eurocode 9 (European code for design of aluminium structures), GB50017-2003 (Chinese Code for design of steel structures) and GB50429-2007 (Chinese Code for the design of Aluminium Structures). The experiment column curve was then derived and compared with the curves of columns of different codes. Lastly a comparison between the present test results and the results of Rasmussen and Rondal (2000) [1] is presented. [ABSTRACT FROM AUTHOR]

Material constitutive relationship is one of the basic problems for analysis and application of aluminum alloy structures. This paper systematically studied the material constitutive model of the domestic high-strength new grade aluminum alloy 6082-T6. Tensile testing was conducted for a total of 90 coupons that were cut from three cross-section shapes of the aluminum alloy 6082-T6. The measurement and statistical analysis of mechanical parameters were carried out, including non-proportional extension strengths, tensile strength, elastic modulus, breaking elongation, Poisson's ratio, etc. Various methods for calculating hardening exponent n in the Ramberg-Osgood law were discussed. The fast simulated annealing (FSA) method for calculating n was proposed and the FSA code was written to obtain the confidence interval of n. Comparison of results between FSA and other methods indicates that the FSA can provide more stable results than the traditional two-point method. On this basis, the material constitutive model of the 6082-T6 aluminum alloy was obtained. The comparison of this model and the tested stress-strain curve demonstrates that the constitutive model has good accuracy and can be applied to the engineering applications of aluminum structures. [ABSTRACT FROM AUTHOR]

To provide reliable verification and guidance for experiments, numerical simulations of 17 high-strength aluminum alloy columns in compression were conducted using ABAQUS and the results were compared with experimental results. Factors which influenced simulation results, including meshes size, thickness of end plates, initial imperfection and material properties were analyzed. 3D full integration continuum element C3 D20 and Ramberg-Osgood model for stress-strain relationship were adopted in simulation. The simulation results show that the relative errors of buckling load between experiments and simulations are under 12%; the meshes size and thickness of end plates have a negligible influence on stability coefficient, and the existence of end plates rarely influence mechanical properties of specimens with hinge supports; as initial geometric imperfection ascends and the parameter n of aluminum alloy descends, the value of stability coefficient decreases; buckling loads of specimens obviously increases as proof stress f0.2 increases, especially for specimens with small slenderness ratio. [ABSTRACT FROM AUTHOR]

Aluminum alloy shells are increasingly used in public buildings as a supporting structure for roofing enclosure construction in large spaces. In performance-based fire protection design, an empirical design criterion of 150 °C and relevant empirical formulas are used; however, the safety margin and prediction effect are not verified through full-scale experiments, and therefore, the effect of the roof system on the near-roof temperature field in practical engineering is yet to be investigated. In this study, a simulated fire experiment was conducted using a cylindrical aluminum alloy reticulated roof system model. The heat release rate of this restricted fuel fire source during the stable burning stage reached 8.1 MW. Fire Dynamics Simulator (FDS) was used to reproduce experimental results, and the numerical model of the shell member was simplified; further, existing empirical formulas of scholars such as Li were compared. The results indicated that although 150 °C is a large safety margin, it may limit architectural function. The simplified shell model provides an effect-equivalent approach for building thin-walled members in FDS. The shell is the main factor that delays the time required for the near-roof space to reach thermal equilibrium. The existing empirical formulas cannot be used for the studied roof system directly, and they may be improved through coefficient adjustment and other such methods. • First fire test of full-scale aluminum alloy arched roof system. • 150 °C critical criterion in performance-based design has a large safety margin. • Thermal equilibrium moment prolonged by aluminum alloy shell members. • Existing empirical formulas cannot be used to predict studied roof system. [ABSTRACT FROM AUTHOR]

• New joint for connecting aluminum rectangular hollow section members is proposed. • Six different full-scale ARH joints are tested under an out-of-plane bending moment. • The M-Φ curves, stress variation, and failure modes of the ARH joint are obtained. • A bilinear model is proposed to summarize the M-Φ curves of the joint. • The influence of different factors on mechanical behavior of ARH joints is analyzed. A new joint system for connecting aluminum alloy rectangular hollow section (ARH) members is proposed to overcome the problem of connecting rectangular tubes using the traditional Temcor joint. The structural performance of the ARH joint system under an out-of-plane bending moment is studied experimentally. The moment-rotation (M-Φ) curves, stress variation, and failure modes of the ARH joint obtained from the tests are discussed. A bilinear model is proposed to summarize the M-Φ curves of the joint. The influence of the key parameters, gusset thickness and bolt quantity on the mechanical behavior of the ARH joint is analyzed. Subsequently, finite element analysis is conducted to investigate the moment rotational behavior of the ARH joint. The comparison between the experimental and numerical results proves that the proposed finite element model is accurate enough and can be used to study the moment resistance behavior of the ARH joint system. The results show that the proposed ARH joint, for connecting rectangular hollow section members, can be considered as a semi-rigid connection. This study provides a reference for the practical application of the ARH joint in reticulated structures made of aluminum rectangular members. [ABSTRACT FROM AUTHOR]

• Tests of the two joint systems under out-of-plane and in-plane bending were conducted. • FE model of the two joint systems was established and verified. • The M-Φ curves and failure modes of the two joints were obtained, compared and discussed. • Parametric analysis is carried out to study the mechanical behavior of the new joint. • Different loading combinations of axial force and bending were considered during analysis. The static behavior of the traditional aluminum alloy Temcor (AAT) joint system and a new aluminum alloy hollow prism-plate (AHP) joint system is studied experimentally. The bending moment-rotation curves and failure modes for the two joint systems under out-of-plane bending (M x) and in-plane bending (M y) are obtained. The test results indicate that the bending stiffness and carrying capacity of the new hollow prism-plate (AHP) joint is superior to that of the traditional Temcor (AAT) joint. The refined finite element model (FEM) of the two kind of aluminum alloy joint systems are established based on a large-scale finite element analysis software. The simulation results are verified by comparing with the experimental results. Finally, to investigate the mechanical behavior and force transfer mechanism of the new hollow prism-plate (AHP) joint system, the parametric analysis is carried out to obtain the moment-rotation (force-displacement) curves and failure modes of the joint system under different loading conditions, including axial compression force, axial tension force, bending with compression force, and bending with tension force. [ABSTRACT FROM AUTHOR]