Nonlinear analysis of plate–truss composite steel girders

An efficient approach to the nonlinear analysis of plate–truss composite steel girders is presented in this paper. Using finite strip elements in transverse direction, a spatial displacement field in consideration of local buckling of a plate–truss composite structure is constructed. The updated Lagrangian formulation of the finite strip element is introduced based on the incremental virtual work principle of the three-dimensional continuum, and the effect of large deformation is taken into account with the Euler coordinate transformation. The effect of material nonlinear behavior is considered with inner-force plastic coefficients of cross section. As an illustrating example of the application of the presented approach, the nonlinear behavior of a plate–truss composite steel bridge model is studied, and the computational results are verified with test data.