تقرير
Spatial Poisson processes for fatigue crack initiation
| العنوان: | Spatial Poisson processes for fatigue crack initiation |
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| المؤلفون: | Babuska, Ivo, Sawlan, Zaid, Scavino, Marco, Szabó, Barna, Tempone, Raúl |
| سنة النشر: | 2018 |
| المجموعة: | Physics (Other) Statistics |
| مصطلحات موضوعية: | Statistics - Methodology, Physics - Data Analysis, Statistics and Probability, 62N05, 74B05, 62M30, 60G55, 62N01, 62M05, 62P30 |
| الوصف: | In this work we propose a stochastic model for estimating the occurrence of crack initiations on the surface of metallic specimens in fatigue problems that can be applied to a general class of geometries. The stochastic model is based on spatial Poisson processes with intensity function that combines stress-life (S-N) curves with averaged effective stress, $\sigma_{{\mathrm{eff}}}^{\Delta} (\mathbf{x})$, which is computed after solving numerically the linear elasticity equations on the specimen domains using finite element methods. Here, $\Delta$ is a parameter that characterizes the size of the neighbors covering the domain boundary. The averaged effective stress, parameterized by $\Delta$, maps the stress tensor to a scalar field upon the specimen domain. Data from fatigue experiments on notched and unnotched sheet specimens of 75S-T6 aluminum alloys are used to calibrate the model parameters for the individual data sets and for their combination. Bayesian and classical approaches are applied to estimate the survival-probability function for any specimen tested under a prescribed fatigue experimental setup. Our proposed model can predict the initiation of cracks in specimens made from the same material with new geometries. |
| نوع الوثيقة: | Working Paper |
| DOI: | 10.1016/j.cma.2018.11.007 |
| الوصول الحر: | http://arxiv.org/abs/1805.03433Test |
| رقم الانضمام: | edsarx.1805.03433 |
| قاعدة البيانات: | arXiv |
| DOI: | 10.1016/j.cma.2018.11.007 |
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