In the Karaganda coal basin, deteriorating geomechanical conditions have been observed, including seam disturbances, diminished strength of argillite–aleurolite strata, water ingress, and pronounced floor heave, all of which markedly increase the labor intensity of maintaining developmental headings. The maintenance and operation of these entries for a reference coal yield of 1000 t necessitate 72–75 man-shifts, of which 90–95% are expended on mitigating ground pressure effects and restoring support integrity. Conventional heave control measures—such as relief drifts, slotting, drainage, secondary blasting, and the application of concrete or rock–bolt systems—deliver either transient efficacy or incur prohibitive labor and material expenditures while lacking unified methodologies for predictive forecasting and support parameter design. This study therefore advocates for an integrated framework that synergizes geomechanical characterization, deformation prognosis, and the tailored selection of reinforcement schemes (incorporating both sidewall and floor-anchoring systems with directed preloading), calibrated to seam depth, geometry, and lithological properties. Employing deformation state assessments to optimize reinforcement layouts for floor stabilization in coal mine workings is projected to curtail repair volumes by 30–40% whilst significantly enhancing operational safety, efficiency, and the punctuality of face preparation.
6 September 2022 in Kompleksnoe Ispolzovanie Mineralnogo Syra = Complex Use of Mineral Resources
This article presents possible reasons for the low productivity of wells for coal methane extraction and ways to resolve them using hydrochloric acid treatment of wells. A common reason for the low productivity of wells is a decrease in the permeability of the bottom-hole formation zone. Starch, calcium carbonate, and drilling rocks, which are part of the drilling mud, change the filtration properties of the layer during the formation of a filtration crust and lead to a decrease in the initial permeability. Hydrochloric acid treatment, during which clay rocks are dissolved, is an effective method of increasing the productivity of wells. It is used to increase pick-up and prevent contamination of the bottom-hole zone of the carbonate formation. The parameters affecting the effectiveness of hydrochloric acid treatments were considered. The results of the experience of the interaction of hydrochloric acid with a clay crust are presented and analyzed using approaches to the mechanics of multiphase media. Dependences of the rate of dissolution of clay rock on the concentration of acid solution are obtained. It is established that the treatment of the productive intermediate layer of the well with hydrochloric acid in a certain concentration, its use increases the technological and economic efficiency of wells. As a result of experimental work, it was found that hydrochloric acid with an HCL concentration above 18% has a negative effect on the internal equipment of the well when processing clay shells.
The development of mining operations in high-altitude regions is associated with a number of geomechanical challenges caused by increased rock fracturing, adverse climatic conditions, and high seismic activity. These issues are particularly relevant for the exploitation of gold ore deposits, where the stability of open-pit slopes directly affects both safety and extraction efficiency. The aim of this study is to develop and practically substantiate a comprehensive approach to assessing and ensuring slope stability, using the Bozymchak gold ore deposit—located in a high-altitude and seismically active zone—as a case study. The research involves the laboratory testing of rock samples obtained from engineering–geological boreholes, field shear tests on rock prisms, laser scanning of pit slopes, and digital geomechanical modeling. The developed calculation schemes take into account the structural features of the rock mass, geological conditions, and the design contours of the pit. In addition, special bench excavation technologies with pre-shear slotting and automated GeoMoS monitoring are implemented for real-time slope condition tracking. The results of the study make it possible to reliably determine the strength characteristics of the rocks under natural conditions, identify critical zones of potential collapse, and develop recommendations for optimizing slope parameters and mining technologies. The implemented approach ensures the required level of safety.
The development of a geomechanical model is aimed at enhancing the safety of mining operations through the determination of optimal slope angles and the probabilistic assessment of pit wall stability. For the conditions of open-pit mining, three-dimensional geomechanical models were constructed based on the calculation of the slope stability factor using the Rocscience Slide2/Slide3 (v.9.027, 2023) software package. The stress–strain state of the rock mass at the final stage of extraction was evaluated using the finite element method. Strength reduction factors (SRF) were determined considering the physico-mechanical properties of the rocks forming the near-contour zone of the massif. The stability of the pit slopes was assessed along individual geological cross-sections in accordance with the design contours of the Northern Katpar open pit. Calculations performed using several methods confirmed the overall stability of the pit walls. The final design parameters of the projected open pit were determined. For the first time, it was established that in the southern and southwestern sectors of the Northern Katpar pit, within the elevation range of +700 to +400 m, a reduction in the SFR (from 1.18 to 1.41) occurs due to the predominance of siltstones and the presence of tectonic disturbances. The generalized results of numerical slope stability analyses for the design pit contour, together with the developed geological–structural model of the deposit, provide a basis for ensuring the safe conduct of mining operations at the site.
10 May 2025 in Mining informational and analytical bulletin
This article is devoted to the crucial actual problem of the restoration of lands disturbed by the mining industry. It has been determined that before the reclamation of disturbed lands, it is essential to conduct an environmental impact assessment. The main objective of the research is to find and study the most optimal methods for reducing the technogenic impact of the mining industry on the environment by restoring disturbed areas. The object of the study was a mining enterprise in the Karaganda region. The Karaganda region was chosen for the study due to being the one with the most mining industry. After the extraction of mineral resources, the territories of the region became the most vulnerable and required the clearest solution for land restoration, taking into account the physical and geographical conditions. The work includes a statistical analysis of historical data on the state of disturbed territories of the Karaganda region, and laboratory and field studies. The comprehensive study revealed a clear need to restore disturbed lands. This will prevent further degradation of land resources and will make it possible to use them for new agricultural purposes. For the first time, studies were conducted for various soils, including technogenic soils, typical for areas where mining enterprises are located. For the first time, a reclamation algorithm has been developed for a mining enterprise in the Karaganda region, taking into account engineering and geological surveys.