Design of rock bolt-based goaf edge support for conventional depillaring with stowing

0548145 - ÚGN 2022 RIV DE eng J - Journal Article
Ram, S. - Singh, A. K. - Kumar, R. - Kumar, A. - Kumar, N. - Waclawik, Petr - Gautam, A. - Raja, M.
Design of rock bolt-based goaf edge support for conventional depillaring with stowing.
Arabian Journal of Geosciences. Roč. 14, č. 21 (2021), č. článku 2164. ISSN 1866-7511. E-ISSN 1866-7538
Institutional support: RVO:68145535
Keywords : rockbolt * conventional depillaring * stowing * caving * numerical modelling * rock load height * goaf edge support
OECD category: Mining and mineral processing
Impact factor: 1.827, year: 2020
Method of publishing: Limited access
https://link.springer.com/article/10.1007/s12517-021-08379-3

Rock bolts have replaced the conventional cog/chock as roof support from underground coal mines working with continuous miner (CM) technology in Bord and Pillar mining method with caving system. Rock bolts installed in the gallery at the goaf edge by aligning the adjacent stable rib during the CM-based mechanised depillaring have proven its potential by restricting goaf encroachment towards the working area. However, conventional depillaring with stowing and caving system still uses skin-to-skincog/chock as goaf edge support in Indian coalfields which poses threat to the safety of miners during its erection and withdrawal. Further, bearing capacity of such goaf edge support also reduces with increase in height of working. Field study found that the adjacent in-bye rib of the working slice remains intact and stable due to less span of hanging roof inside the goaf during conventional depillaring with stowing compared to caving. These field outcomes are also validated during the numerical simulation and observed that the goaf edges are over-supported in a stowing panel as it adopted the similar goaf edge support pattern as that of caving. Further, a parametric study is conducted on numerical models by varying the nature of roof, gallery width, and depth of cover to estimate the rock load height (considering 1.5 safety factor contour) around the goaf edges in stowing panels. Multivariate regression analysis was carried out to establish a relationship among influencing parameters for estimation of rock load height at the goaf edges in stowing panels for a given geo-mining condition. This paper presents a novel design of rock bolts as goaf edge support on the basis of roof-rib interaction in conventional depillaring with stowing panel.
Permanent Link: http://hdl.handle.net/11104/0324256