NUMERICAL SIMULATION OF LOCALIZED DEFORMATION FIELD FOR ROCK IN PLANE STRAIN STATE
平面应变岩样局部化变形场数值模拟研究

Deformation field in relation to shear strain localization, such as shear strain rate, volumetric strain rate, velocity and displacement for rock material undergoing elastic and strain softening stage, was studied by FLAG3D. A reprocessing code programmed by FISH was developed to show the distributed shear strain and displacement in the form of three-dimensional curved surface, which contributed to understanding of strain localization phenomena. The inclination angle of shear band and its width increase as dilatation angle is increased. The extent of localized deformation decreases as dilatation effect is considered. The increase of the inclination angle of shear band and its width has an opposite influence on stress-strain curve of specimen after localization occurs. Two conjugate shear bands divide the specimen into four small blocks, which have properties of movement of rigid body. In every small block, the displacement field is uniform, and in the edge of the shear band the field has large spatial gradient. The location of shear strain rate localization coincides in position with the location of volumetric strain rate, which is the actual failure zone of rock.