Process for the protection against falling rocks or coal from the face breast during underground gallery driving

摘要

For the process for protection against falling rocks or coal from the face breast during underground gallery driving by covering the face breast with a plastic sheet through which the blast holes are drilled and the blasting charges are inserted and tamped down, while the detonating wires are connected in front of the sheet, it is proposed to use a plastic sheet which has holes of 5 to 10 cm diameter over the entire surface.