Analysis of the Effect of Uncertain Clamping Stiffness on the Dynamical Behaviour of Structures Using Interval Field Methods

Abstract:

In uncertainty calculation, the inability of interval parameters to take into account mutual dependency is a major shortcoming. When parameters with a geometric perspective are involved, the construction of a model using intervals at discrete locations not only increases the problem dimensionality unnecessarily, but it also assumes no dependency whatsoever, including unrealistic parameter combinations leading to results that probably overestimate the true uncertainty. The concept of modelling uncertainty with a geometric aspect using interval fields eliminates this problem by defining basis functions and expressing the uncertain process as a weighted sum of these functions. The definition of the functions enables the model to take into account geometrically dependent parameters, whereas the coefficients in a non-interactive interval format represent the uncertainty. This paper introduces a new type of interval field specifically tailored for geometrically oriented uncertain parameters, based on a maximum gradient condition to model the dependency. This field definition is then applied to a model of a clamped plate with uncertain clamping stiffness with the purpose of identifying the effects of spatial variability and mean value separately.

• Periodical: Applied Mechanics and Materials (Volume 807)
• Pages: 195-204
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.807.195
• Online since: November 2015
• Authors: Maurice Imholz*, Dirk Vandepitte, David Moens
• Keywords: Interval Analysis, Interval Fields, Possibilistic Analysis, Uncertainty Modelling

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