Boundary value problems in plastic flow of random media

Research output: Contribution to journalConference article

Abstract

Effects of spatial random fluctuations in the yield condition of rigid-perfectly plastic continuous media are analyzed in cases of a Cauchy boundary value problem and a characteristic boundary value problem. Plastic material is assumed to be isotropic and hence it is described by a random field of plastic limit k, which is taken as space-homogeneous, ergodic, and having a high signal-to-noise ratio. The solution method is based on a stochastic generalization of the method of slip-lines, whose significant feature is that the deterministic characteristics are replaced by the forward evolution cones. Comparisons of response of this random medium and a deterministic homogeneous medium with a plastic limit equal to the average of k are carried out in specific examples of the two boundary value problems under study. It is found that the weak material randomness always leads to a relatively much stronger scatter in the position and field variables. In cases of inhomogeneous boundary data the sensitivity of field quantities to the strength of randomness of plastic limit k is very high and amplifies the differences between the average solution of a stochastic problem and the solution of the homogeneous medium problem.

Original languageEnglish (US)
Pages (from-to)149-158
Number of pages10
JournalAmerican Society of Mechanical Engineers, Applied Mechanics Division, AMD
Volume135
StatePublished - Jan 1 1992
Externally publishedYes
EventASME Summer Mechanics and Materials Conferences - Tempe, AZ, USA
Duration: Apr 28 1992May 1 1992

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Plastic flow
Boundary value problems
Plastics
Cones
Signal to noise ratio

ASJC Scopus subject areas

  • Mechanical Engineering

Cite this

Boundary value problems in plastic flow of random media. / Ostoja-Starzewski, Martin.

In: American Society of Mechanical Engineers, Applied Mechanics Division, AMD, Vol. 135, 01.01.1992, p. 149-158.

Research output: Contribution to journalConference article

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