On the Computational Aspects of a Symmetric Multidomain Boundary Element Method Approach for Elastoplastic Analysis

摘要

The symmetric boundary element method (SBEM) is applied to the elasto-plasticudanalysis of bodies subdivided into substructures. This methodology is based on the use of: audmultidomain SBEMapproach, for the evaluation of the elastic predictor; a return mapping algorithmudbased on the extremal paths theory, for the evaluation of inelastic quantities characterizing theudplastic behaviour of each substructure; and a transformation of the domain inelastic integrals of eachudsubstructure into corresponding boundary integrals. The elastic analysis is performed by using theudSBEM displacement approach, which has the advantage of creating system equations that onlyudconsist of nodal kinematical unknowns at the interface boundary among substructures. The elastoplasticudsolution utilizes a strain-driven strategy that is characterized by the evaluation of the elasticudpredictor that is a function of the initial conditions and the load increment. The predictor phase isudfollowed by the use of a returnmapping algorithm defined by introducing the extremal paths theoryudto remove the time integration. Then the computed plastic strains are considered to be constantudinelastic actions imposed inside the substructure in a step-by-step procedure. Their presenceudinvolves domain integrals with singular kernels. These integrals are considered as Cauchy principaludvalues with which the related free term is associated. In order to compute these domain integrals, theudradial integral method is applied to remove the strong singularity.