Abstract
The purpose of present study is to develope a new beam-column model based on modified complementary energy principle, considering the validity of the force method for the problem of material non-linearity. As its first report, a new plane beam-column model for elasto-plastic and collapse analysis is proposed in this paper. This model satisfies completely both equilibrium and compatibility conditions for any states of stiffness distribution and load, namely has no discretizing error. Therefore, if the evaluation of stiffness and energy integration are accurately carried out, the exact solutions can be gained in every range. Also, application of the plastic hinge method to this modelcan be simply put in operation by the Lagrange multiplier. A series of analysis have duly proved that this model might be very powerful for the problem of material nonlinearity.
