The finite deformation theory for beam, plate and shell Part I. The two-dimensional beam theory Original Research Article

A finite deformation theory is proposed that can describe precisely, the nonlinear geometric behavior of a two-dimensional beam structure. Unlike the existing nonlinear theories, this theory does away with simplifications such as the assumptions of small displacement, small normal or shearing strain, small rotation, as well as small loading step. The finite element method and its formulation of this theory are deduced. Numerical examples performed by the theory proved it valid and computed results obtained by the theory are independent of loading steps.