72 / 2023-03-31 20:21:26

POINT-SPATIAL MODELING OF GEOMECHANICAL PROCESSES OCCURRING DURING OPEN-PIT MINING OF COAL DEPOSITS

OPEN-PIT MINING,GEOMECHANICAL PROCESSES,COAL DEPOSITS,pit edge massif

In the world at present, in order to achieve efficient and safe operation in open-pit coal mining, monitoring should be carried out with the involvement of specialists of various profiles. The role of the surveyor in this system is invaluable, since it must provide information such as the observed parameters of the quarry, the results of observations of shifts and deformations of massifs, the calculation of mineral reserves, and the geometry of dumps. The available modern data on deposits are insufficient for surveying services to control geomechanical processes in the pit edge massif of quarries, as well as to predict their condition by analyzing and evaluating the extraction of mineral deposits in difficult conditions of occurrence. For more accurate control and forecasting, it is necessary to take into account such important factors as the study of geology, tectonics, dynamics of the mining area and the study of processes before the start of mining operations based on the data obtained and the creation of geomechanical models that reflect the actual state of the mining areas.

In the Republic of Uzbekistan, special attention is paid to the development of coal industry enterprises, especially research, development of forecasting methods, assessment of the condition and forecast of the stability of the pit edge massif in connection with the deepening of mining operations in landslide-deformation zones based on surveying and geodetic monitoring and spatial-point modeling.

In this connection, the assessment of changes in the stress-strain state of the Valley-Foothill system, the pit edge massif, was carried out using the modeling of geomechanical processes by the finite element method, on the basis of which horizontal and vertical displacements and the formation of tectonic stress fields in the field area were predicted before the start of mining operations.

Studies have revealed that the valley floor in the area of the deposit has a height of up to 1020 m, and the height of the foothills reaches more than 3000 m. above sea level. The scheme of the model provides for a cross-section of the valley with foothills, with a maximum slope height of 2000 m.

As a result of modeling, it is proved that geomechanical processes in the formation of landslide phenomena have a genetic connection with the "geological memory" of rocks involved in the landslide process, namely, in the manifestation of the first crack in the body of rocks that make up the landslide array.

Studies of the stability of the landslide sections of the Angrensky coal mine were carried out along profile lines.

Stability was evaluated according to the condition K_min ≥ K_S, (K_min is the minimum calculated coefficient of stability margin for the most dangerous sliding surface) using the Solidworks Premium SP1.0.2019 program, the algorithm of which provides for the layering of the array and the selection of various sliding lines in the form of arcs of circles with the search for the most dangerous sliding surface. At the same time, the program also takes into account the seismic impact on the board and determines the stability by three methods (G.Kray, K.Terzagi, weight pressure).