Research of segregation zones of marginal rocks for prediction the rigidity of rocks roof and sides of mine workings

The article presents the results of an experimental remote control of assessment of stress-strain state of rock mass destroying the roof and sides of working displacements by deformation monitoring instruments, which has carried out a visual control over the segregations in the massif as well as the massif displacement and segregation in the marginal rocks of mine working have been estimated quantitatively. The authors conducted production monitoring of mine working rigidity during different periods of service life and application in the mines of the Karaganda coal basin fixed by different types of supports. Modes of operation of the combined support with metal-frame support with rigid anchors were investigated. The parameters of deformation processes close to the working at their location in the impact area of second working were defined. On the basis of statistical processing of experimental data, the regularities of deformation processes and empirical dependences on the influencing factors were determined. The analytical modeling for prediction the stress-strain state of technogenic space for the establishment of durability (the time to failure and evaluation of sustainability in the excavation working depending on the depth of the mine working with the change of controllability of enclosing rocks) was carried out. The results of the analytical and experimental studies have demonstrated their relative convergence with respect to the deformation characteristics. It is advisable to use a roof bolting for a more complete use of the bearing capacity of the combined support and increase the rigidity of mine working in bearing pressure zone. Anchors bind individual lowly cohesive rock layers into a single load-carrying structure of composite plate, thereby increasing coupling and friction between the layers. Additional friction occurs due to anchors tension between the layers of rocks. At the same time, the rigidity of the composite plate tightened by anchors across the layers approaches to the rigidity of the monolithic rock mass. Carried out research of technological segregation zones in marginal rocks for prediction the rigidity of rock top and sides of mine working allowed to establish the degree of influence of mining and technological factors on the effectiveness of the rock anchor application in the excavation working.