Effect of High Horizontal Stress on Coal Mine Entry Intersection Stability.
Hanna K; Haramy KY; Conover DP; Dopp D
Proc 5th Conf Ground Control Ming Morgantown West Virginia, 1986 Jun; :167-182
This manuscript describes an extensive ground control study at the Inland Steel No. 2 Mine near McLeansboro, Illinois, conducted by the Bureau of Mines in cooperation with Inland Steel Coal Company. The mine experiences severe ground control problems primarily due to high horizontal stress, particularly at entry intersections. Mine experience has shown that reorienting mine entries, modifying the bolting pattern, and altering the mining sequence are effective in reducing the severity of roof falls and out-of-seam dilution. However, the frequency of roof falls has not been significantly reduced. This research project was designed to provide a thorough explanation of the intersection failure mechanism through combined analyses of company in-mine experience and Bureau field measurements. Stresses and deformations were monitored in a four- way intersection during all stages of development and were related to site observations and theoretical analyses.
Proc. 5th Conf. Ground Control Ming. Morgantown, West Virginia, June 11-13, 1986, PP. 167-182