GEOMETRICALLY NONLINEAR TRANSIENT ANALYSIS OF PLANE STEEL FRAMES USING A COROTATIONAL UPDATED LAGRANGIAN FORMULATION
Palavras-chave:
Geometrical nonlinearity, Second-order effects, Nonlinear transient analysis, Updated Lagrangian description, Corotational approach.Resumo
The objective of this research is to present a study of the influence of the geometrical
nonlinearities in the dynamic behavior of plane steel frames. The adopted geometrically nonlinear
formulation is based on Euler-Bernoulli model and uses the updated Lagrangian description and the
corotational approach to deduce the tangent stiffness matrix of the element with both fixed ends. The
theory predicts that nodes will suffer large displacements and rotations, and the elements of the
structure, large stretches and curvatures. The solution of the nonlinear equations of motion is achieved
by combining the Newmark's implicit time integration method with the Newton-Raphson technique.
The results of the performed analyzes showed a good agreement with the numerical solutions available
in the literature, demonstrating the efficiency of the proposed method in obtaining the geometrically
nonlinear dynamic behavior of steel structures.
