A reformulation of the static approach to evaluate directly the shakedown and limitmultipliers by using the Symmetric Boundary Element Method for multidomain type problems[1,2] is shown. The present formulation utilizes the self-equilibrium stress equation [3-5]connecting the stresses at the Gauss points of each substructure (bem-e) to plastic strains through astiffness matrix (self stress matrix) involving all the bem-elements in the discretized system. Thenumerical method proposed is a direct approach because it permits to evaluate the multiplierdirectly as lower bound through the static approach. The analysis has been performed as acostrained optimization problem, solved through mathematical programming methods. In thisapproach the optimization problem has been rephrased in the canonic form of a ConvexOptimization, in terms of discrete variables, and implemented by using Karnak.sbem code coupled with the MatLab.
|Numero di pagine||4|
|Stato di pubblicazione||Published - 2012|