Slashchova O.A., Slashchov І.M., Sapunova I.O. Specific solution of problem of water filtering in the rocks by the finite element method
- Details
- Parent Category: Geo-Technical Mechanics, 2019
- Category: Geo-Technical Mechanics, 2019, № 146
Geoteh. meh. 2019, 146, 140-150
https://doi.org/10.1051/e3sconf/201910900093
SPECIFIC SOLUTION OF PROBLEM OF WATER FILTERING IN THE ROCKS BY THE FINITE ELEMENT METHOD
1Slashchova O.A., 1Slashchov І.M., 1Sapunova I.O.
1Institute of Geotechnical Mechanics named by N. Poljakov of National Academy of Sciences of Ukraine
UDC 622.831.31
Language: English
Abstract.
The article is devoted to development of methods for geofiltration calculations with taking into account peculiarities of changes of the rock physical and mechanical properties at water saturation. Methods: mathematical modeling of geomechanical and filtration processes with the help of finite element method and laboratory and underground studies. A mathematical model was formulated for solving a problem of elasticity theory by the finite element method, which took into account peculiarities of water-saturated rocks. Pattern of stress-strain state changing in the fractured water-saturated rocks under the action of critical loads, which occurred around the preparatory roadways during their operation, were established. In order to improve reliability of results of calculations, it is necessary to take into account concrete mining and geological conditions through testing minimum number of samples or conducting limited amount of geophysical measurements. In order to solve the filtration problems, a bank of collected initial data on physical and mechanical properties of water-saturated rocks was processed with the help of variation coefficients, which were taken into account by the method, which assumed calculation of the model loading with critical parameters. Processing of results of instrumental measurements at the stations and comparing the data obtained at watering and without watering shows that floor displacements increase over time by linear dependencies and feature close correlation. Water saturation of the floor rocks demonstrates its maximum effect on stability of the roadway floor during the first 20 days; this fact is confirmed by data of laboratory experiments on the time characteristics of reduced strength of watered rocks. Application of preliminary floor consolidation under the studied conditions reduces relative displacements by 20-40% depending on the volume of water input and depth of the consolidated zone. Therefore, the following actions should be undertaken: to regulate water inflow into the floor during technological operations; to make operational assessment of water effect on the rock strength properties adapted to specific mining and geological conditions and technology; to develop parameters for methods of the mine workings floor consolidation with taking into account water saturation.
Keywords: water-saturated rocks, physical and mechanical properties of rocks, stress-strain state, floor stability of mine workings.
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About the authors
Slashchovа Olena Anatoliivna, Candidate of Technical Sciences (Ph.D), Senior Researcher, Senior Researcher in the Department of Mineral Mining at Great Depths, Institute of Geotechnical Mechanics named by N. Poljakov of National Academy of Sciences of Ukraine (IGTM, NAS of Ukraine), Dnipro, Ukraine, This email address is being protected from spambots. You need JavaScript enabled to view it.
Slashchov Ihor Mykolaiovych, Candidate of Technical Sciences (Ph.D), Senior Researcher, Senior Researcher in Department of Mineral Mining at Great Depths, Institute of Geotechnical Mechanics named by N. Poljakov of National Academy of Sciences of Ukraine (IGTM, NAS of Ukraine), Dnipro, Ukraine, This email address is being protected from spambots. You need JavaScript enabled to view it.
Sapunova Iryna Oleksandrivna, Candidate of Technical Sciences (Ph.D), Senior Researcher, Senior Researcher in Department of Mineral Mining at Great Depths, Institute of Geotechnical Mechanics named by N. Poljakov of National Academy of Sciences of Ukraine (IGTM, NAS of Ukraine), Dnipro, Ukraine, This email address is being protected from spambots. You need JavaScript enabled to view it.