Overburden deformation due to longwall mining; its development and final distribution.
Ingram DK; Trevits MA; Jeran PW
Proceedings of the International Land Reclamation and Mine Drainage Conference and Third International Conference on the Abatement of Acidic Drainage April 24-29, 1994, Pittsburgh, Pennsylvania. Pittsburgh, PA: United States Department of the Interior, Bureau of Mines, Special Publication SP 06C-94, 1994 Apr; 4:337-344
The objective of this U.S. Bureau of Mines investigation was to characterize overburden response due to longwall mining. Subsurface strata and surface deformations were monitored during the mining of two adjacent longwall panels in southeastern Ohio. Multipoint borehole extensometers (MPBX) with eight anchors were installed in six boreholes across both panels to measure subsurface displacements. Survey monuments were installed along the center lines and profile lines over both panels to measure surface deformations. During the mining of the first panel, subsurface displacements occurred in a radiating pattern beginning just above the extracted area in the center of the panel and extending upward and outward towards the surface and margins of the panel. Overburden deformation did not project over the gate road entries. During the mining of the second panel, the MPBX's showed almost simultaneous displacement, indicating that the overburden moved as a unit. Again, overburden deformation was confined to the immediate panel area. At both panels, overburden movement began when the longwall face was approximately 25% of the overburden thickness beyond the line of MPBX boreholes.
Author Keywords: subsidence; coal mine subsidence; coal mining; overburden deformation; longwall mining
Proceedings of the International Land Reclamation and Mine Drainage Conference and Third International Conference on the Abatement of Acidic Drainage April 24-29, 1994, Pittsburgh, Pennsylvania