Dynamic events at longwall face, CSM Mine, Czech Republic

0532516 - ÚGN 2021 RIV AU eng C - Conference Paper (international conference)
Waclawik, Petr - Němčík, J. - Kukutsch, Radovan - Gong, Libin - Venticinque, G.
Dynamic events at longwall face, CSM Mine, Czech Republic.
Proceedings of the 2020 Coal Operators Conference. Wollongong: University of Wollongong - Mining Engineering, 2020 - (Aziz, N.; Kininmonth, B.), s. 233-241. ISBN 978-1-74128-320-4.
[Coal Operators Conference 2020. University of Wollongong (AU), 12.02.2020-14.02.2020]
R&D Projects: GA MŠMT(CZ) EF16_027/0008478
Institutional support: RVO:68145535
Keywords : rockburst * dynamic * longwall
OECD category: Mining and mineral processing
https://ro.uow.edu.au/coal/

Presented here are the details of the seismic events that occurred at longwall 11 located at the CSM mine in the Ostrava coal region, Czech Republic. This longwall was
excavated in a very complex area located within the shaft protective pillar and adjacent to the 50 m wide and steeply inclined fault zone at a depth of 850 m. In addition, 10 longwalls were
extracted below each other over many years in several sloping seams located on the other side of the large sloping fault zone resulting in complex stress fields and large subsidence. The
immediate roof above longwall 11 was a very strong sandstone and sandy siltstone with an uniaxial compression strength of 80 – 160 MPa. When the longwall started, continuous seismic monitoring of the longwall area indicated 470 small seismic events with energy smaller than <102 J. The first high energy event of 3.3*105 J occurred when the longwall advanced 85m past
the starting line. Some 30 minutes later a rockburst occurred registering energy of 2.2 *106 J, causing significant rockburst damage at the tailgate located near the large tectonic zone. The roadway steel arches were significantly deformed and the maximum floor heave reached up to 1.5 m. To investigate the complex strata behavior in that area, a large FLAC3D model 0.27 km3
in volume was constructed and 10 longwalls were extracted in several sloping seams adjacent to the large fault zone. The model under construction is now ready to study the complex strata behaviour and the associated stress fields together with the dynamic strata behaviour to match the modelled seismic events with those measured underground.

Permanent Link: http://hdl.handle.net/11104/0310989