Mining Publication: Optimum Mine Designs to Minimize Coal Bumps: A Review of Past and Present U.S. Practices
Coal bumps have presented serious mining problems in the United States throughout the 20th century. Fatalities and injuries have resulted when these destructive events occur at the working face. Persistent bump problems can result in abandonment of large reserves or lead to premature mine closure. Through the years, alternative techniques such as artificial supports, extraction sequencing, destressing, pillar design changes, and specific pillar retreat practices have been successfully implemented to mitigate coal mine bumps. Several techniques have evolved for room-and-pillar operations that control the way the roof rock breaks, regulating the manner in which stresses are redistributed in the mined section. Special mine layouts employed in longwall mines have also proved to be successful in safely redistributing or containing excessive loadings. However, with ever-increasing production rates, greater overburdens, and new mining systems, the need to evolve even more effective bump control designs will continue to challenge the U.S. coal industry.