BLAST-DAMPING BULKHEAD Russian patent published in 2001 - IPC

FIELD: mining industry; applicable in performance of blasting operations for damping of air shock waves in mine workings, protection of underground structures and service lines. SUBSTANCE: bulkhead is made of flexible bands freely hanging from roof of mine working and crossing main part of working cross-section. Bands are woven from synthetic threads. Planes of the first rows of bands source of air shock waves are oriented parallel to direction of wave propagation along longitudinal axis of working. Planes of bands of subsequent rows are oriented at an angle to working longitudinal axis. In so doing, direction of angle in each subsequent row of bands changes to opposite one. Angles of inclination of band planes to working longitudinal axis rise in direction of propagation of air shock waves, and all bands of the last rows are oriented with their planes square to working longitudinal axis and direction of propagation of air shock waves, and length of the last rows of bands exceeds working height. End parts of excessive length of bands lie on working floor. Excessive length of bands shall cover the main part of working cross-section area after blasting of charges of all series of delay and in inclined state produced by air shock waves. EFFECT: reliable damping of air shock waves, reduced weight of bulkhead and unified bulkhead flexible members. 2 dwg