ABSTRACT
The micro-structural change which causes material strength deterioration is usually termed damage. This chapter introduces a new theory in rock mechanics-damage mechanics of rock. It provides three basic facts for the establishment of a damage analysis model of rock materials. Damage mechanics was first applied to rock materials by Dougill et al. Microstructural observations of rock materials indicate that rock damage can be responsible for the strain-softening effect, so that the rock’s material laws are non-monotone in nature, and its super-potential functions are non-convex. The Lianyuan area in China is serially depressed by northwest-southeast lateral compression, and can be analyzed by geological data relative to the structural character of the region. In underground engineering, the balance of stress in surrounding rock is disturbed after mining, so that rock movement, deformation, damage and fracture occur, particularly under longwall cavings. The chapter presents non-smooth deformation at the fracture bed is clearly characterized by the non-smooth mechanics theory.
