KATEDRA ZA MEHANIKU  MAŠINSKOG FAKULTETA U NIŠU

VAS POZIVA DA UČESTVUJETE U RADU

SEMINARA
TEORIJSKE I PRIMENJENE MEHANIKE

U   Petak, 5. decembra  2003. godine  sa početkom  u 10,15 časova u sali 401

MILOŠ KOJIĆ ,
Ph. D., Professor, Faculty of Mechanical Engineering, University of Kragujevac
Research Scientist, Harvard School of Public Health, Harvard University
IVO VLASTELICA,
Ph. D., Professor, High Technical School, Čačak

odžaće predavanje

APPLICATION OF THE GENERAL ALGORITHM FOR 3-D DEFORMATION OF THE GURSON ELASTIC-PLASTIC MATERIAL TO SMALL AND LARGE STRAIN SHELL CONDITIONS

 Abstract: An implicit stress integration procedure for the Gurson material model – the metal plasticity with volumetric plastic strain – and for large strain shell deformation is outlined in the paper. The stress calculation is based on the governing parameter method (GPM), with the increment of the mean plastic strain   used as the governing parameter. The shell condition (the zero stress through shell thickness) is satisfied at the end of time (load) step and the stresses are determined by solving the nonlinear equation with respect to  .
It is outlined how the small strain stress calculation procedure can be extended to the large strain shell deformations. The large strain formulation assumes the multiplicative decomposition of the deformation gradient and the logarithmic strains. This extension is based on a simple implementation of the 3-D kinematics relations to the shell conditions.
A numerical example, the large strain plastic bulging of a circular plate, illustrates applicability of the proposed numerical procedure for stress integration.