粒状体の誘導異方性について

Abstract

The stress-induced anisotropy is one of the most important mechanical properties of granular materials. This paper proposes a new theory on this property. First, the features of the induced anisotropy are summarized and how to measure the anisotropy is described explaining the fabric tensor and defining the inductivity degree of anisotropy α. The proposed theory is based on the theory of space-mapping by a tensor, and the property that the force-line graph tends to coincide with the particle graph under a monotonic loading is assumed. This property is considered a most remarkable property in the induced anisotropy. From the proposed theory α=0.5 is derived, that agrees well with the experiment results. The modified stress is defined from the theory and it is shown that, in the granular materials, the ordinary stress is shared by the anisotropy of contact normals and the modified stress.