Inelastic Second-Order Analysis of Frame Structures Using the Stability-Based Beam-Column Element

In this study. the stability-based beam-column element has been proposed to consider the geometric second-order effects and material inelasticity, and to take advantage of the computational efficiency of the second-order analysis. A new force interpolation function matrix is developed to consider a moment magnification due to the axial force and lateral displacement. The constitutive behaviour of the cross-section is formulated by integration of the uniaxial stress-strain response of fibres to model the material inelasticity. The generalized displacement control (GDC) method incorporating the incremental secant stiffness method is applied to solve the nonlinear equilibrium equations with multiple limit points. Evaluation of the results of this Study shows that the proposed method consistently predicts well the nonlinear inelastic behaviour of steel and composite structures, and gives good efficiency.