Updated Lagrangian Co-rotational Formulation for Geometrically Nonlinear FE Analysis of 3-D Beam Element

To improve the precision and efficiency of computations for a structure with a large displacement and rotation,an updated Lagrangian co-rotational formulation for geometrically nonlinear FE(finite element) analysis of 3-D beam elements was proposed.With this method,a standard updated Lagrangian formulation is adopted to build the equilibrium equations of a beam element,the tangent stiffness matrix is derived from the principle of minimum potential energy,the computational procedure for large rotation is applied to compute new coordinates of elements and nodes,and the rigid displacement is taken away from the total displacement to get strain-producing deformations to obtain the precision increment of internal forces.Finally,two numerical examples were given to testify the correction and precision of this method.