Reliability sensitivity evaluation of randomly excited linear structures with uncertain parameters isaddressed. The excitation is modeled as a stationary Gaussian random process. Uncertainty affectingstructural parameters is handled within a non-probabilistic framework by applying the interval model.Under the assumption of independent up-crossings of a specified threshold, a procedure for the analyticalderivation of interval reliability sensitivity is presented. The key idea is to perform stochastic analysis inthe frequency domain by applying the improved interval analysis via extra unitary interval in conjunctionwith a novel series expansion of the inverse of an interval matrix with modifications, herein called IntervalRational Series Expansion (IRSE). This approach yields approximate explicit expressions of intervalresponse statistics and structural reliability along with their sensitivities with respect to the uncertainparameters. Reliability sensitivities provide useful information to increase the safety level and can be alsoexploited in the context of first-order interval Taylor series expansion to estimate the bounds of intervalreliability when slight uncertainties are involved. A wind-excited truss structure with interval stiffnessproperties is analyzed to show the effectiveness of the proposed procedure.
|Titolo:||Explicit reliability sensitivities of linear structures with interval uncertainties under stationary stochastic excitation|
SOFI, Alba (Corresponding)
|Data di pubblicazione:||2015|
|Appare nelle tipologie:||1.1 Articolo in rivista|