Journal of the Southern African Institute of Mining and Metallurgy
On-line version ISSN 2411-9717
WANG, X. et al. Evaluating the coal bump potential for gateroad design in multiple-seam longwall mining: A case study. J. S. Afr. Inst. Min. Metall. [online]. 2015, vol.115, n.8, pp. 755-760. ISSN 2411-9717. http://dx.doi.org/10.17159/2411-9717/2015/V115N8A12.
This study proposes a methodology for evaluating the risk of coal bumps in multiple-seam longwall mining. Both the stress field and the total energy release (TER) during retreat were evaluated in the specified case involving multiple-seam mining using the LaModel program. The results of numerical simulations indicated that both the peak vertical stresses on the panel edges and the peak TERs in the outby longwalls increased significantly as the horizontal offsets were reduced from 60 m to zero. With the comprehensive consideration of the stress field and TERs, a conservative offset of 60 m was ultimately adopted when developing the gateroads of the lower panel in the field. The field measurements indicated that coal bumps were avoided completely by employing the proposed design, and the maximum roof-to-floor and rib-to-rib convergences of the tailgate during retreat were only 360 mm and 576 mm, respectively.
Keywords : coal bump; total energy release (TER); longwall mining; multiple-seam.