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Approximate dynamic responses in random media

  • G. Dasgupta
Part of the Acta Mechanica book series (ACTA MECH.SUPP., volume 3)

Summary

Stochastic constitutive properties are important in real-world dynamic analyses. The unconventional field equations, with spatially varying random coefficients, pose a computational challenge. For mild stochasticity, straightforward perturbations yield satisfactory response statistics. On the other hand, large statistical deviations can be captured from infinite sequence approximations, with a stationary iteration scheme introduced by Boley. For coupled thermal and elastodynamic random field problems, only the “inversions” of the uncoupled operators pertaining to a uniform continuum are deemed adequate. Stochastic boundary element approximations follow directly from the proposed stochastic Green’s functions. In the light of Tatarski’s wave considerations, corresponding stochastic finite element formulations require additional convection like spatially random terms related to stochastic shape functions. Crucial aspects of dynamic computations with random material properties are summarized here with sample numerical examples.

Keywords

Boundary Element Random Medium Monte Carlo Simulation Technique Stochastic Operator Truss Member 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Wien 1992

Authors and Affiliations

  • G. Dasgupta
    • 1
  1. 1.Department of Civil Engineering and Engineering MechanicsColumbia UniversityNew YorkUSA

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