A New Definition of Damage Variable for Rock Material Based on the Spatial Characteristics of Deformation Fields

Abstract

Considering with the spatial characteristics of concentrated deformation field caused by the micro-cracks concentration and localization in rock, a new damage variable is defined based on the standard deviation of the strain fields of rock specimen surface during loading. When digital speckle correlation method (DSCM) is used to measure the deformation fields of rock specimen, the damage variable definition in this paper takes great advantages on damage measurement of rock methods. Using the new methods, the damage of rock would be measured for the whole loading process and the experiment is easy to be implemented. The validity of the proposed damage variable is verified by the experimental results on column-shaped marble specimen subject to uniaxial compression.