Improving Methods of Frozen Wall State Prediction for Mine Shafts under Construction Using Distributed Temperature Measurements in Test Wells
- 1 — Mining Institute of the Ural Branch of the RAS
- 2 — Mining Institute of the Ural Branch of the RAS
- 3 — Mining Institute of the Ural Branch of the RAS
Abstract
Development of mineral deposits under complex geological and hydrogeological conditions is often associated with the need to utilize specific approaches to mine shaft construction. The most reliable and universally applicable method of shaft sinking is artificial rock freezing – creation of a frozen wall around the designed mine shaft. Protected by this artificial construction, further mining operations take place. Notably, mining operations are permitted only after a closed-loop frozen section of specified thickness is formed. Beside that, on-line monitoring over the state of frozen rock mass must be organized. The practice of mine construction under complex hydrogeological conditions by means of artificial freezing demonstrates that modern technologies of point-by-point and distributed temperature measurements in test wells do not detect actual frozen wall parameters. Neither do current theoretical models and calculation methods of rock mass thermal behavior under artificial freezing provide an adequate forecast of frozen wall characteristics, if the input data has poor accuracy. The study proposes a monitoring system, which combines test measurements and theoretical calculations of frozen wall parameters. This approach allows to compare experimentally obtained and theoretically calculated rock mass temperatures in test wells and to assess the difference. Basing on this temperature difference, parameters of the mathematical model get adjusted by stating an inverse Stefan problem, its regularization and subsequent numerical solution.
References
- Amosov P.V., Lukichev S.V., Nagovitsyn O.V. The Influence of Rock Mass Porosity and Cooling Agent Temperature on the Speed of Solid Frozen Wall Formation. Vestnik Kol'skogo nauchnogo tsentra RAN. 2016. N 4 (27), p. 43-50 (in Russian).
- Bulychev N.S., Komarov D.S., Lukashin S.B. Calculation of Necessary Frozen Wall Parameters in the Hinge Part. Izvestiya TulGU. Estestvennye nauki. 2012. Iss. 1, Part. 2, p. 54-60 (in Russian).
- Gendler S.G. Complex Safety Provision in the Development of Mineral and Spatial Subsoil Resources. Gornyi zhurnal. 2014. N 5, p. 5-6 (in Russian).
- Levin L.Yu., Semin M.A., Parshakov O.S.Mathematical Method of Frozen Wall Thickness Prediction in Mine Shaft Development. Fiziko-tekhnicheskie problemy razrabotki poleznykh iskopaemykh. 2017. N 5, p. 154-161 (in Russian).
- Levin L.Yu., Semin M.A., Zaitsev A.V. Solution of the Inverse Stefan Problem in the Analysis of Ground Water Freezing in the Rock Mass. Inzhenerno-fizicheskii zhurnal. 2018. Vol. 91. N 3, p. 655-663 (in Russian).
- Levin L.Yu., Semin M.A., Parshakov O.S., Kolesov E.V. Method of Solving the Inverse Stefan Problem to Control Frozen Wall State in the Process of Mine Shaft Construction. Vestnik Permskogo natsional'nogo issledovatel'skogo politekhnicheskogo universiteta. Geologiya. Neftegazovoe i gornoe delo. 2017. Vol. 16. N 3, p. 255-267 (in Russian).
- Maslak V.A., Bezrodnyi K.P., Lebedev M.O., Gendler S.G. New Engineering Solutions for Subway Tunnels in a Metropolitan City. Gornyi zhurnal. 2014. N 5, p. 57-60 (in Russian).
- Parshakov O.S. Developments of an Approach to Formation and State Monitoring of a Mine Shaft Frozen Wall. Strategiya i protsessy osvoeniya georesursov: Sb. nauch. tr. Perm': GI UrO RAN, 2017. Iss. 15, p. 288-292 (in Russian).
- Tarasov V.V., Pestrikova V.S. Review of Accidents on Verkhnekamsk Potassium Deposit in the Process of Mine Shaft Construction. Gornyi informatsionno-analiticheskii byulleten' (nauchno-tekhnicheskii zhurnal). 2015. N 5, p. 23-29 (in Russian).
- Trupak N.G. Rock Freezing in Shaft Development. Мoscow: Ugletekhizdat, 1954, p. 896 (in Russian).
- Andersland O.B., Ladanyi B. An introduction to frozen ground engineering; Springer US. 1994, p. 352. ISBN 9781475722925
- Gol'dman N. Inverse Stefan Problems. Springer Science & Business Media. 2012. 412 p.
- Gilyazov S.F., Gol'dman N.L. Regularization of ill-posed problems by iteration methods; Kluwer Academic PublishersGroup. Dordrecht, 2000, p. 350.
- Hu J., Wang X., Jiang B. Numerical Analysis of Temperature Field of Vertical Frozen Soil Wall Reinforcement at Shield Shaft. Advanced Materials Research. 2014. Vol. 918, p. 218-223.
- Kabanikhin S.I., Hasanov A., Penenko A.V. A gradient descent method for solving an inverse coefficient heat conduction problem. Numerical Analysis and Applications. 2011. Vol. 1. Iss. 1, p. 34-45. DOI: 10.1134/S199542390
- Vitel M., Rouabhi A., Tijani M., Guerin F. Modeling heat transfer between a freeze pipe and the surrounding ground during artificial ground freezing activities. Computers and Geotechnics. 2015. N 63, p. 99-111.
- Vyalov S.S., Zaretsky Yu.K., Gorodetsky S.E. Stability of mine workings in frozen soils. Engineering Geology. 1979. Vol. 13, p. 339-351.
- Wang J., Liu X., Chen H. Freezing large shaft design of about one kilometer deep. Journal of Glaciology and Geocryology. 2012. Vol. 34(6), p. 1358-1363.
- Zhang B., Yang W., Wang B. Plastic Design Theory of Frozen Wall Thickness in an Ultradeep Soil Layer Considering Large Deformation Characteristics. Mathematical Problems in Engineering. 2018, p. 10. DOI: 1-10.1155/2018/8513413