Materiały konferencyjne SEP 1993 - tom 2

Szkoła Eksploatacji Podziemnej '93 RFTTER LAYpUT DESIGN CRITERIA Criterion Application ERR Energy Release Rate Stress: strength ESS Exce5S Shear Stress w:h Width:height ratio APS Average pillar stress RCF Rockwall condition factor Seismicity in longwall situations Selection of support systems Bracket pilfar design, dykes Magnitude of shear-type events Remedial measures (qualitative) Pillar design, including stabilizing piliars Siting and support of sefvtce excavations EFFECT OF ENERGY RELEASE RATE ON MINING CONDITIONS 10 MJ/ni» (Iow ERR) / 50 MJ/m» (high ERR) \ 4 ERR correlates with Practłcal significance 1 Stresses In front of face 2 Shear stresses on planes of weakness 3 Oepth & height of face fracturlng 4 Dilation of fracture zone & thrust on h/w beam 5 Stopę convergence behind face Drilling difficulties, crush bursting Face-parallel shear seismic events "Hard patches" on fece. Seismic "cushion" of fractured rock Hangingwałl stability Mining conditions, generated support resistance Sekcja III 119