Numerical experiments to assess the performance of different formulations and solution algorithms for geometrically nonlinear analysis of two-dimensional frames

Resumo

This work presents an investigation, through numerical experiments, of different geometrically
nonlinear formulations and solution algorithms for the structural analysis of two-dimensional frame models. The
goal is to determine the most suitable formulation and algorithm to be adopted for structural analyses of this type.
The formulations investigated for the tangent stiffness matrix of beam-column elements are based on different
kinematic descriptions of motion, namely the Updated Lagrangian and Corotational approaches. The algorithms
to solve the nonlinear system of equations are continuation methods based on the standard Newton-Raphson
iteration strategy commonly used to suppress limit points of load and displacement. The numerical experiments
cover a wide variety of simple benchmark models, each one with a distinct nonlinear behavior, to evaluate the
performance of the formulations and algorithms selected for this study.