Water effect on the rocks and mine roadways stability

Yalanskyi

et al. 2022

The article covers a live scientific problem consisting in development of new and improving of existing digital technologies for forecasting a stress-strain state of ultimate stressed rock massif. The analysis of the researches has shown that the approaches based on the synthesis of mine monitoring methods and analytical forecasting methods are promising for assessing the state of ultimate stressed rocks. The existing hazard indicators can be beaded by the integral indicators of the stress-strain state of the rock massif determined with the help of geo-information systems. However, there are no methods, algorithms and software for figuring these indications. As a result of the research, methods of implementation and functions of software elements have been developed for determining integral indicators characterizing the state of an ultimate stressed rock massif. The “Methodological recommendations …” have been developed, which describes specificity of using the information system for forecast integral parameters of the rock massif stress-strain state and assessing the conditions for the rock destruction. The use of the designed methods, algorithms and software decreases geomechanical risks of gas-dynamic phenomenon occurrence, reduces cost of breakdown elimination and increases economical efficiency of the mining enterprises.

Section: Resultsmentioning

confidence: 99%

Development of methods and software algorithms for state forecast of the ultimate stressed rock massif

Yalanskyi

et al. 2022

“…The scientific foundations of the technology of active management of the state of the rock mass have been developed at IGTM NASU. An analytical description of the stress-strain state of the rock mass near the working excavation [4,5,[12][13][14][15][16][17][18], including taking into account: free gas in the rocks, water saturation and man-made cracks [7,[19][20][21], geological disturbances [7], extreme deformation of rocks [4,5], physicochemical destruction of coal [22] is worked out by scientists of the institute. A model, which has been verified by numerous experiments in mines, has been developed.…”

Section: Methodology Of Mathematical Modelingmentioning

confidence: 99%

New technical solutions in the field of protection and fastening of mine workings

Yalanskyi

Makeiev

et al. 2022

The article discusses the features of fastening preparatory workings in difficult geological conditions, which are studied in three directions: improving concrete, arch and anchor fasteners with the consideration of the initial physical and mechanical properties of the rock mass; introduction of steel-polymer anchor; improvement of cast strips designs in combination with arch and anchor fasteners for reuse. Protection methods of mine workings and means of fastening often do not correspond to the peculiarities of the manifestation of rock pressure at the end sections of lavas and in zones of tectonic disturbances, as a result of which can become the main cause of the unsatisfactory state of the mine workings. Mathematical modeling of the rock massif stress-strain state has been carried out by the finite element method. Rigid and pliable cast strips, various technologies for erecting a cast strip, as well as a combination of cast strips with anchor and arch fasteners are modeled. The locations and sizes of rocks destruction zones, stresses in the rock mass for different options of fastening have been determined. The drawbacks of the existing technologies for the construction of cast strips are revealed and the factors for increasing their technical efficiency are established.

“…Radon and its decay products, as well as methane gas, easily penetrate porous and fractured rocks. Therefore, in mine roadways, the amount of methane and radon depends on the stress-strain state and the permeability of the rock massif [16][17][18][19][20]. Monitoring of specificity of radon decay product and methane gas emission it possible to forecast the risks of mine roadways destruction.…”

Section: Features Of the Radon And Methane Gas Decay Products Emissio...mentioning

confidence: 99%

Forecast of the mine workings destruction risks by the radiometric control method

Bielikov

Kulbach

et al. 2023

Self Cite

The stress-strain state of the rock mass affects the content of methane gas and radon aerosols in the atmosphere of mine workings. Therefore, combined control of methane gas and radon in mine workings allows us to monitor changes in the state of the rock massif and to take measures in proper time to reduce the risks of the roadway destruction. Forecasting of rock massif and mine roadway dangerous state is based on the determined features of methane gas emission together with radon decay products into the mine roadways radon decay products. Interdependence between the dynamics of changes in the concentration of methane gas and the normalized concentration of radon is established when range of the deviations from the average value is ± 20%. Abrupt spikes at the range above 40% are explained in prone-to-destruction zones of the rock massif. One of the indicators of the rock massif readiness for dynamic manifestations of rock pressure and the destruction of mine roadways can be a decrease in the concentration of radon decay products Po218 below 5%.