SURFACE DEFORMATION CHARACTERISTICS ABOVE UNDERMINED AREAS: EXPERIENCES FROM THE EASTERN UNITED STATES COALFIELDS.

Damage resulting from surface movements due to underground mining may range from simple land settlement to severe structural damage. Since subsidence prevention is not feasible, it is important that accurate ground movement prediction techniques are developed, so that damage due to underground mining as well as the amount of coal lost due to the protection of surface structures can be minimized. To facilitate the mitigration of the deleterious effects of subsidence in the Eastern U. S. region, empirical subsidence prediction techniques for longwall mining were developed from 45 case studies collected within the coalfield. From these subsidence prediction techniques a strain prediction model was also formulated. These subsidence and strain prediction methods can be used to predict ground movements as part of the mining plan and to evaluate the impacts of underground mining on the surface.