DETERMINATION OF ROCK DESTRESSING PARAMETERS AT THE ENDS OF DISASSEMBLING ROOM

The coal mining industry in Russia distinctively gravitates toward increasing output of fully-mechanized longwall faces. With gain in productivity of longwall mining equipment, the diseconomies of its outage also grow. There can be many reasons for the downtime of the fully mechanized longwall faces. The idle time in re-assembly is avoidless; thus, it is highly important to minimize such idle time in order to improve performance of mines. The main causes of increase in the reassembly time include roof falls in working areas. Roof falls are the most intensive at the ends of disassembling rooms. One of the efficient techniques to enhance roof rock stability is stress relaxation. This study aims to determine parameters of immediate roof rock destressing in disassembling rooms in thick and gently dipping coal seam mining based on the finite-element geomechanical model. The article presents the geomechanical modeling procedure (computational schemes) for assessment of stress state in rock mass around a disassembling room. The parameters of the limiting state zones in coal seam and in roof rocks of the disassembling room are estimated. The parameters of the method for the immediate roof rock unloading from high stresses at the ends of the disassembling room by distress blasting are substantiated. The governing parameters of the technologies include: destress zone width, destress hole diameter, length and spacing, as well as drilling time before longwall approach.


For citation:  Karpov G. N., Kovalski E. R., Smychnik A. D. Determination of rock destressing parameters at the ends of disassembling room. MIAB. Mining Inf. Anal. Bull. 2019;(8):95-107. [In Russ]. DOI: 10.25018/0236-1493-2019-08-0-95-107.

Keywords

Gently dipping coal seams, underground coal mining, longwall equipment disassembling, disassembling room, rock mass unloading, immediate roof stability, stress state, destress holes.

Issue number: 8
Year: 2019
ISBN: 0236-1493
UDK: 622.2
DOI: 10.25018/0236-1493-2019-08-0-95-107
Authors: Karpov G. N., Kovalski E. R., Smychnik A. D.

About authors: G.N. Karpov (1), Cand. Sci. (Eng.), Assistant Professor, e-mail: prk42@mail.ru, E.R. Kovalski (1), Cand. Sci. (Eng.), Assistant Professor, e-mail: e.r.kovalsky@gmail.com, A.D. Smychnik, Dr. Sci. (Eng.), Professor, OOO K-Potash Services, Russia, e-mail: suma35799@gmail.com. 1) Saint Petersburg Mining University, 199106, Saint-Petersburg, Russia. Corresponding author: G.N. Karpov, e-mail: prk42@mail.ru.

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