Reliability of Elasto-Plastic Structural Systems

This paper proposes a method for generating safety margins and failure mode equations for elasto-plastic structures where interaction of load effects is taken into account. Structural failure is defined by large nodal displacements or plastic collapse. A branch-and-bound technique is used to identify the significant failure modes. For non-linear yield conditions equivalent linear models obtained by linearization of the yield function at the design point are used. A displacement based limit state is used where the deflections are determined using an incremental elasto-plastic analysis taking into account interaction of load effects and load path dependence.