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DOE OSTI · 1391856

Frequency analysis of uncertain structures using imprecise probability

Modares, Mehdi·Bergerson, Joshua
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Abstract

Two new methods for finite element based frequency analysis of a structure with uncertainty are developed. An imprecise probability formulation based on enveloping p-boxes is used to quantify the uncertainty present in the mechanical characteristics of the structure. For each element, independent variations are considered. Using the two developed methods, P-box Frequency Analysis (PFA) and Interval Monte-Carlo Frequency Analysis (IMFA), sharp bounds on natural circular frequencies at different probability levels are obtained. These methods establish a framework for handling incomplete information in structural dynamics. Numerical example problems are presented that illustrate the capabilities of the new methods along with discussions on their computational efficiency.

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97 MATHEMATICS AND COMPUTINGImprecise ProbabilityP-BoxStructural DynamicsUncertainty

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Modares, Mehdi, Bergerson, Joshua. 2015-01-01. Frequency analysis of uncertain structures using imprecise probability. https://doi.org/10.1504/ijrs.2015.073126

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