Stoppings for ventilating coal mines.
Kawenski-EM; Mitchell-DW; Bercik-GR; Frances-A
Pittsburgh, PA: U.S. Department of the Interior, Bureau of Mines, RI 6710, 1965 Sep; :1-20
Tests were made in the Bureau of Mines Experimental Coal Mine on stoppings similar to those used in operating coal mines to obtain information on air leakage through the face and the rupture strength of a stopping subjected to a pressure differential. Block stoppings were made from cinder, slag, and gravel aggregates with and without mortared joints and coatings. Sheet stoppings were uncoated brattice cloth and nylon or brattice cloth and expanded metal-lath coated with asphalt, latex, mortar, or rigid urethane foam. Limited data were obtained on air leakage through stoppings subjected to simulated roof convergence and to shock forces created by the firing of an adjacent charge of explosive. The pressure differential required to rupture stoppings was determined. The research shows that coating the face of a stopping effectively reduces air leakage. Block stoppings, particularly those with mortared joints, are most resistant to pressure and shock forces than are sheet stoppings. Where ground movement is a factor, sheet stoppings leak less air than block stoppings.
Mining-industry; Mine-shafts; Underground-mining; Coal-mining; Ventilation; Ventilation-systems
Report of Investigations
Pittsburgh, PA: U.S. Department of the Interior, Bureau of Mines, RI 6710