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arXiv · 1501.03956

Characterization of random stress fields obtained from polycrystalline aggregate calculations using multi-scale stochastic finite elements

Bruno Sudret·Hung Xuan Dang·Marc Berveiller·Asmahana Zeghadi·Thierry Yalamas
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Abstract

The spatial variability of stress fields resulting from polycrystalline aggregate calculations involving random grain geometry and crystal orientations is investigated. A periodogram-based method is proposed to identify the properties of homogeneous Gaussian random fields (power spectral density and related covariance structure). Based on a set of finite element polycrystalline aggregate calculations the properties of the maximal principal stress field are identified. Two cases are considered, using either a fixed or random grain geometry. The stability of the method w.r.t the number of samples and the load level (up to 3.5 % macroscopic deformation) is investigated.

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Bruno Sudret, Hung Xuan Dang, Marc Berveiller, Asmahana Zeghadi, Thierry Yalamas. 2015-01-16. Characterization of random stress fields obtained from polycrystalline aggregate calculations using multi-scale stochastic finite elements. https://arxiv.org/abs/1501.03956

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