CONSIDERATION OF CORRELATIONS BETWEEN MATERIAL PROPERTIES IN A SPECTRAL STOCHASTIC ELASTO-PLASTIC MODEL

Abstract

Efficient treatments of correlations between material properties are important for the risk analysis of the ground because there are the correlations in soil. This paper proposes an approach to consider correlations between material properties in a stochastic elasto-plastic model with the spectral method. In the approach, the spectral expansion is performed on correlated parameters of material properties by applying the principal axis transformation. Increasing degrees of freedom is a practical problem when taking into account both spatial correlations and correlations between material properties. It can be avoided by considering spatial correlations of only the ?rst primary component of strongly correlated material properties. We simulate stochastic stress-strain relations of an elasto-plastic body in which the elastic modulus correlates to the strength. It is shown that the approach enables efficient evaluations of behaviors of elasto-plastic bodies with the correlated material properties despite the complex behaviors. It is difficult to predict the uncertainty of responses from one of the material properties without evaluations of the probabilistic yield process. Therefore, simulations considering correlations between material properties are essential for the risk quanti?cation of the ground.