Rock Mechanics Studies in a Mechanized Longwall Coal Mine.
Ch 12 Proc 2D Int conf on Stability in Underground Min Lexington Kentucky 1984 :189-209
Methods and results of measuring three basic parameters for ground stability control -- ground pressure, strata movement, and geomechanical properties of mine rock -- are presented. It was found that these parameters can be measured in situ by simple and practical techniques with nonsophisticated and inexpensive instruments. Specifically, a drillhole dilation technique employing a cylindrical hydraulic borehole pressure cell (cpc) was used to determine the modulus of rigidity. Premining ground pressures were determined by pressure convergence tests with a combination of one cpc and two pre-encapsulated flat hydraulic borehole pressure cells (bpc) installed in a single drillhole. Abutment pressures and pillar loading were monitored with bpc. Differential strata movements and bed separations were measured with self-recording 10- anchor-point extensometers. Roof-to-floor convergence was measured with self-recording convergence meters. Some applications of these in situ-determined parameters to mine design and ground stability control are also discussed.
Ch.12 Proc. 2D Int.conf. on Stability, in Underground Min., Lexington, Kentucky, 1984, PP. 189-209