Materiały konferencyjne SEP 1993 - tom 1

Underground Exploitation Schcx>l '93 In rcference to the traditional undeground coal-seams mining we have made the investigation to define the influence of geodynamic prpcesses on the effectiveness of A mining. Mine measurements have shown that each mine field consist of some blocks, characterized by different level of geodynamic activity. It was establish- ed thet the horizontal voltage component in the central Donbass region is 2,2 - 4 times higher than the vertical one. It confirms the fact» that rock pressure is the result of not only gravitational forces action, but it is the result of tectonic and some other forces of extemal origin (for example, astronomical influence). The investigations have indicated that technico-economical indexes of woiic at mining districts, the slability of mine workings and burst safety of coal seams depends essenially on their position relatively to the vector of peak voltages. It permitted to develop the science-substantiated recommendations on the choice of rational parameters of coal-seams mining, with the accoount of mine field geodynamics and tectonic fissuring of rock mass. The techniąues were elaborated and tested at a number of mines with the steep and flat seams occurence, which help to establish the geodynamic activity of rock mass on the basis of geodynamic mapping. The parameters of rock fissuring are defined at blocks with different activity, the Yoltage is measured and vector of total stress tensor and it's vertical and horizontal components are defined. The result of mine measurements and calculations are used as the basis for the elaboration of specifics technical and technological proposals, aimed at the raise of the effectiyenens of mining and it's safety under the condition given. These proposal are as follows: the choice of rational direction of coal field mining and it's separate areas; the choice of the rational disposition of the opening and the development of workings (mine shafts, pit-bottom workings, crosscuts, main haulage horizontal roads and inclines workings); the choice of safe direction of the development workings conduction in the seams, subjected to the sudden coal and gas bursts; the prove of the effective form of cross-section of mine workings and their supports; rational parameters of mining methods (the length of the working face, it's disposition in space on the account of the rock mass fissuring and the application of coal-extraction technology); effective coal-extraction technology (the mode of coal getting, ways of using longwall support system, roof control, ways of safety protection). These recomendation provide the improvement of technico-economical indexes of coal extraction and the decrease of traumation: the output per face grows in 10-30%, the expenses for timbers decrease in 1%, face advance increases in 20-25%. Depending from particular mining and geological conditions the expenditures on mine workings maintenance decrease in 2 or 3 times but the safety of mining works increases. The expenses for the maintenance of undeground workings diminish. 236 Tom I