Krukovskyi O.P., Krukovska V.V. Stress state and filtration permeability of barrier pillars near the isolated fire area

Geoteh. meh. 2018, 142, 3-12

https://doi.org/10.15407/geotm2018.142.003

STRESS STATE AND FILTRATION PERMEABILITY OF BARRIER PILLARS NEAR THE ISOLATED FIRE AREA

KrukovskyiO.P., KrukovskaV.V.

Authors:

Krukovskyi O.P., Corresponding Member of NAS of Ukraine, Doctor of Technical Sciences (D. Sc) (IGTM, NAS of Urraine)

Krukovska V.V., Doctor of Technical Sciences (D. Sc), Senior Researcher (IGTM, NAS of Urraine)

UDC 622.267.5

Language: Russian

Annotation.

During fires, composition of atmosphere in the coalmines is changed drastically: content of oxygen decreases, while content of carbon dioxide, carbon monoxide, hydrogen and of other gases increases. According to the regulatory requirements, coal-face operations near the fire area can be performed only with remained barrier pillars, whose width should be calculated with two ensured conditions: pillars stability and gas impermeability. In the article, a numerical study of stress state and filtration permeability is performed for the coal-rock massif with isolated area, active mine working and barrier pillar. Finite-element models of the coal-rock massif with mine workings, between which barrier pillars with different widths are remained, are developed. With the help of finite element method, stress fields and zones with inelastic deformation were calculated. Calculations were performed for three widths of the pillars installed between the mine workings: 20 m, 30 m and 40 m. Based on geomechanical calculations, fields of permeability coefficients, distributions of gas pressure and gas leaks in the area under the study were calculated. Graphs of pillar permeability change in the undisturbed zone and tectonically disturbed zone were constructed. It is shown that with pillar width of 20 m, filtration areas around the isolated space and active working are connected with both the coal seam and enclosing rock. At a certain rate of pressure drop, fire gas filtration from the isolated space into the active working is possible. When width of pillar is 30 m, filtration areas around the isolated space and mine working are not connected: there is an impermeable zone between them. In this case, gas filtration through the barrier pillar is hardly possible. When width of pillar was 40 m, length of impermeable zone was increased.

Keywords:

stress state, filtration permeability, fire gas, barrier pillar.

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About the authors:

Krukovskyi Olexandr Petrovych, Corresponding Member of NAS of Ukraine, Doctor of Technical Sciences (D. Sc), Deputy Director of the institute, M.S. Polyakov Institute of Geotechnical Mechanics under the National Academy of Sciences of Ukraine (IGTM, NASU), Dnepr, Ukraine, This email address is being protected from spambots. You need JavaScript enabled to view it. .

Krukovska Viktoriia Viktorivna, Doctor of Technical Sciences (D. Sc), Senior Researcher, Senior Researcher in Department of Control of Dynamic Demonstrations of Rock Pressure, M.S. Polyakov Institute of Geotechnical Mechanics under the National Academy of Sciences of Ukraine (IGTM, NASU), Dnepr, Ukraine, This email address is being protected from spambots. You need JavaScript enabled to view it. .