TY - CONF

T1 - MACRO-ZONES SGBEM APPROACH FOR STATIC SHAKEDOWN ANALYSIS AS CONVEX OPTIMIZATION

AU - Zito, Liborio

AU - Panzeca, Teotista

PY - 2013

Y1 - 2013

N2 - A new strategy utilizing the Multidomain SGBEM for rapidly performing shakedown analysis asa convex optimization problem has been shown in this paper. The present multidomain approach, calleddisplacement method, makes it possible to consider step-wise physically and geometrically nonhomogeneousmaterials and to obtain a self-equilibrium stress equation regarding all the bem-elements of thestructure. Since this equation includes influence coefficients, which characterize the input of the quadraticconstraints, it provides a nonlinear optimization problem solved as a convex optimization problem.Furthermore, the strategy makes it possible to introduce a domain discretization exclusively of zonesinvolved by plastic strain storage, leaving the rest of the structure as elastic macroelements, consequentlygoverned by few boundary variables. It limits considerably the number of variables in the problem andmakes the proposed strategy extremely advantageous. The implementation of the procedure by theKarnak.sGbem code, coupled with optimization toolbox Matlab 7.6.0, made it possible to perform somenumerical tests showing the high performance of the algorithm due to solution accuracy and lowcomputational cost.

AB - A new strategy utilizing the Multidomain SGBEM for rapidly performing shakedown analysis asa convex optimization problem has been shown in this paper. The present multidomain approach, calleddisplacement method, makes it possible to consider step-wise physically and geometrically nonhomogeneousmaterials and to obtain a self-equilibrium stress equation regarding all the bem-elements of thestructure. Since this equation includes influence coefficients, which characterize the input of the quadraticconstraints, it provides a nonlinear optimization problem solved as a convex optimization problem.Furthermore, the strategy makes it possible to introduce a domain discretization exclusively of zonesinvolved by plastic strain storage, leaving the rest of the structure as elastic macroelements, consequentlygoverned by few boundary variables. It limits considerably the number of variables in the problem andmakes the proposed strategy extremely advantageous. The implementation of the procedure by theKarnak.sGbem code, coupled with optimization toolbox Matlab 7.6.0, made it possible to perform somenumerical tests showing the high performance of the algorithm due to solution accuracy and lowcomputational cost.

UR - http://hdl.handle.net/10447/101219

M3 - Other

SP - 1

EP - 6

ER -