Modeling Nonlinear Stress-Strain Behavior of 6000 Series Aluminum Alloys under Cyclic Loading

Prior studies examining the nonlinear material properties of 6000 series aluminum alloys have predominantly concentrated on analyzing the stress-strain characteristics of these materials under monotonic tensile loading. Limited research has been conducted on their behavior under cyclic loading conditions. To address these gaps, a series of monotonic tensile and variable increasing amplitude cyclic loading tests was conducted on coupons made from 6082-T6, 6063-T6, and 6060-T5 aluminum alloys. The experimental results revealed that as strain amplitude increased the material showed isotropic strain hardening. This combined with the adequate hysteretic energy dissipation capacity demonstrates their potential advantage to be used as in structural components in earthquake prone regions. The experimental results are used to calibrate the material parameters of the uniaxial Giuffre-Menegotto-Pinto constitutive model to be able to predict the nonlinear stress-strain behavior under monotonic and cyclic loading. Furthermore, using fiber element modeling in OpenSees software, employing a modified Giuffre-Menegotto-Pinto model, the flexural buckling performance of 6082-T6 aluminum alloy columns is analyzed. The results are compared with existing experimental and finite element data, demonstrating the accuracy of the model in predicting the flexural buckling behavior.