Theory of Strata Mechanics

(abbreviated) Introduction. Development of rock mass mechanics . Interrelation between the mechanics of rock masses and the mechanics of contin uous media. 1. Rock Masses Disturbed by Mining. General characteristics o f rock masses. Idealization of the rock mass. Primary stress state. The equation of continuity. The equation of motion. Concept of weightlessness of a rock. 2. The Elastic State of Rock Around Excavations. The elastic properties of a rock mass. Effect of rock layering upon the form of the equations of state. Equ ation of equilibrium in terms of displacements. Plane state of strain in a rock mass. Systems operating in a plane state of strain. Three-dimensional states of displacement and stress in the vicinity of excavations. 3. The Viscoelastic S tate of Rock Around Excavations. Rheological properties of rock masses. Diff erential form of the state equations. Integral form of the state equations. The displacement equation of equilibrium. Plane strain state. Plane strain- and stre ss distributions around excavations. Three-dimensional stress state around excav ations. 4. Geometrical Theories of Rock Mass Movements. Introduction. The effect of an excavation upon a point isolated on the ground surface. The relati on between the surface of influence and the subsidence profile. The plane profil e of a full subsidence trough. Inclination and curvature of the plane profile of a subsidence trough. Determining the horizontal component of displacement and s train. Variation of the shape of a subsidence trough with time. Three-dimensiona l profile of a subsidence trough with two-parameter surface of influence. Three- dimensional profile of a subsidence trough described by a three-parameter influe nce function. Differential equations for displacements in a rock mass. 5. Ela stic-Plastic Model of an Inhomogeneous Rock Mass. Introduction Elastic-plast ic properties of rocks. The mechanism of elastic-plastic deformation of rocks an d the concept of dislocation. Dislocation energy. Dislocation movement and macro scopic plastic strains. Differential equation describing the average dislocation displacement vector. Dislocation model of a dry rock mass. Equations of the dis location model. General solution of the equations of the dislocation model with account of the anisotropy and inhomogeneity of the rock mass. Solution of the eq uations of the dislocation model for an isotropic, uniformly elastic rock mass. Separating the elastic stress field from the total stress field. One-dimensional distribution of displacement and stress in a rock mass. Estimate of the distri bution of stress in a coal seam. Generalization of the dislocation model. Disloc ation model of a water-saturated rock mass. Effect of local rock swelling. Effec t of local stowing. 6. Theoretical Foundations of Controlling Movements of a Rock Mass . Introduction. Minimization of surface deformations by mining two rectilinear faces simultaneously.