Computation of elastic–plastic plane frames by mathematical programming in case of first, second and third order theory

Paper describes the analysis of the one parameter loading history of frames using a discrete model to characterize the mechanical behaviour of the structure. As a starting point, the geometrically linear behaviour is formulated (first order theory) and then the necessary changes in the formulation are introduced to treat the geometrically nonlinear case. The first case leads to a series of linear complementarity problems and the second case to a series of fully nonlinear programming problems. The application of the method is illustrated by an example solved using the MINOS mathematical programming package.