Stochastic dynamics of linear elastic trusses in presence of structural uncertainties (virtual distortion approach)

Structures involving uncertainties in material and/or in geometrical parameters are referred to as uncertain structures. Reliability analysis of such structures strongly depends on variation of parameters and probabilistic approach is often used to characterize structural uncertainties. In this paper dynamic analysis of linearly elastic system in presence of random parameter variations will be performed. In detail parameter fluctuations have been considered as inelastic, stress and parameter dependent superimposed strains. Analysis is then carried out via superposition principle accounting for response to external agencies and parameter dependent strains. Proposed method yields asymptotic solution which may be applied to whatever coefficient of variation of random structural parameter showing fast convergence increasing number of terms in the asymptotic expansion. Numerical examples illustrate the application of the proposed method to linear elastic truss under dynamic load contrasted with Monte-Carlo solution.