Effect of multiple uncertain material properties on the response variability of in-plane and plate structures

In the majority of research works on stochastic finite element analysis, the main concern is put on the effect of uncertain elastic modulus on the response variability. This is mainly due to the importance of this parameter in the stochastic response of structures but also to the difficulties in introducing other material and/or geometrical uncertain parameters in the stochastic formulation. In this paper, a formulation is suggested in order to determine the response variability of in-plane and plate structures with multiple uncertain material parameters, i.e., elastic modulus and Poisson’s ratio. To accomplish this, use is made of the general equation for nth joint moment and a polynomial expansion on the coefficients of constitutive matrix. For computational purposes, the infinite series of stochastic sub-stiffness matrices is truncated preserving sufficient accuracy. To demonstrate the validity of the proposed formulation, some numerical examples are provided and the results are compared with those obtained by means of classical Monte Carlo simulation combined with the local average scheme.