An approach for design of coal pillars in partial extraction coal mining panels with a consideration of roof-pillar floor extraction /

by Pytel, W. M.
Champaign, IL : Illinois Mine Subsidence Research Program : Illinois State Geological Survey, 1990

An Analysis of roof-pillar-weak floor interaction in partial extraction room-and-pillar mining /

by Pytel, W. M.
Champaign, Ill. : Illinois Mine Subsidence Research Program, Illinois State Geological Survey, 1990

A modified approach for design of coal pillars for weak floor strata conditions /

by Chugh, Yoginder P.
Champaign, IL : Illinois Mine Subsidence Research Program : Illinois State Geological Survey, 1990

Estimation of weak floor strata properties and related safety factors for design of coal mine layouts /

by Pula, O.
Champaign, IL : Illinois Mine Subsidence Research Program : Illinois State Geological Society, 1990