Elastoplastic Analysis of Semi-Rigid Frames Under Cyclic Loading*

摘要

The elastoplastic analysis of semi-rigidly connected steel frames under cyclic loading conditions is performed using a general matrix mathematical programming approach. The finite incremental formulation used for a suitably discretized structure is briefly developed from the three governing relations of equilibrium, compatibility, and constitutive law. Under the assumptions of yielding through generalized plastic hinges that obey piecewise linear yield criteria, small geometry, and quasistatic loading, the analysis for a specified load increment becomes the familiar linear complementarity problem of mathematical programming. The computational scheme used for capturing exactly all hinge activations and un-loadings for a cyclic loading program is described. Numerical examples are given to illustrate application of the approach.