Improving Safety when Extracting Water-soluble Ores by Optimizing the Parameters of the Backfill Mass

Abstract

The results of the scientific and research work devoted to modeling the stress-strain state of the mining system of an underground mine using the finite element method in the FLAC3D software are presented in the article. The possibility of using room-and-pillar mining with backfill with the abandonment of chain pillars is justified. The results are presented concerning the research results of the quantitative assessment of the mass using the von Mises equation and Norton' power law of creep to estimate the contour stress. It becomes possible to determine the sequence of mining of the deposit area and the stage-by-stage filling of the stopes at the stage of mining design due to the high accuracy of modeling the stress-strain state of the mass near mining operations using FLAC3D software. The proposed approach is possible when evaluating the geotechnical state of the rock mass when using the mining systems with various methods of support of the mined-out area: natural; artificial; with the collapse of ores and enclosing rocks, as well as when calculating the combined method of deposit development. A differentiated approach to assessing the state of the mass is possible considering difficult mining and geological conditions, conditions of increased rock pressure, abundant water influx, increased fracturing of rocks by introducing additional conditions into the model depending on its geotechnical state. Variant of the comprehensive exploitation of mineral resources was proposed considering the total value of natural and man-made geo-resources of the area being mined. The possibility of rational use of the mined-out space with the use of various positive qualities of geo-resources at their manmade transformation is also considered. An assessment of the mineral and raw materials potential of the mined area is given with a proposal for the prospects of increasing the integrated approach of excavation, increasing the life of the mining enterprise and the complexity of developing this area.

Thermodynamics and Electrochemistry of the Interaction of Sphalerite with Iron (II)-Bearing Compounds in Relation to Flotation

“…E(ZnS) = −0.6516 + 0.0969pFeOH + , r = 0.954 (10) This proves that Fe 2+ and FeOH + are potential-determining cations, the concentration of which affects the ORP and the potential of the sphalerite electrode. In this case, expressions (7) and (8) show the reducing properties of considered solutions, and approximations ( 9) and ( 10) indicate a possible replacement reaction of Zn 2+ in the sphalerite surface layer for Fe 2+ or FeOH + into solution, leading to the formation of FeS. Further flotation tests of sphalerite samples using thiol collectors confirmed the previous conclusions.…”

“…To provide resources for sustainable development, mining enterprises develop deposits with a low content of a useful component [3] with ores of complex material composition [4] located in difficult mining and geological conditions or near protected objects [5,6]. The depletion of reserves is associated with an increased pressure on the environment in regions with a high concentration of the mining industry [7,8].…”

Back Analysis and Stability Prediction of Surrounding Rock During Excavation of the Shuangjiangkou Underground Powerhouse

“…Ma et al (2020b) and Qian and Zhou (2018) combined finite element simulation and in-situ monitoring to analyze the rock deformation and damage mechanism of surrounding rock during the excavations of the underground powerhouse of the Jinping I hydropower station. Khayrutdinov et al (2021) employed the FLAC3D software to study the stress-strain state of underground mining systems, and proposed a differentiated method which can be used to evaluate the state of rock masses. Ma et al (2016) put forward a stability analysis method for underground caverns that combines numerical simulation and microseismic monitoring, and successfully applied it to an underground sealed storage cavern.…”

Theoretical Analysis of the Influence of Bearing Plate Position on the Bearing Performance of Soil around the CEP Antipull Force Double Pile

“…Thus, the bearing capacity of pile group foundations cannot be simply calculated as an integral multiple of single-pile foundations [14], and the position of the bearing plate is the main factor affecting the bearing capacity of CEP pile groups [15]. This study takes CEP double piles as the research object in an ideal condition, where the influence of the change of soil density during the penetration process of the pile [16,17] and the increase of the load during pile driving on the soil mass is neglected [18,19], sets the important parameter of the bearing plate position, and designs five types of model piles to be divided into six groups for finite element simulation of the same plate position and different plate positions. Compared with ABAQUS software (ABAQUS 2021 versions), ANSYS software (Ansys R19.0 versions) can achieve better simulation in static, quasi-static, and dynamic problems and linear analysis [20]; to this end, it is necessary to establish and address the following objectives and tasks through ANSYS software (Ansys R19.0 versions):…”