Warren, SN, Pakalnis, R, Raffaldi, MJ, Benton, DJ, Sandbak, L & Barnard, CK 2019, 'Ground support design for weak rock mass: quantifying time-dependent closure in squeezing ground', in J Hadjigeorgiou & M Hudyma (eds), Proceedings of the Ninth International Symposium on Ground Support in Mining and Underground Construction
, Australian Centre for Geomechanics, Perth, pp. 169-184.
Mining in weak and highly fractured rock can result in hazardous mining conditions and poses challenges to designing appropriate ground support for the intended use of the excavation. Production levels and infrastructure often require different support strategies because of varying tolerance to time-dependent closure and squeezing ground conditions. This paper presents an empirically derived ground support design methodology that estimates squeeze rate as a function of W-RMR and ground support capacity. This information aids the engineer in designing ground support appropriate to rock mass conditions and intended excavation use, thereby increasing confidence in support design and improving safety in underground mines.
Keywords: mining, ground support, weak rock mass, squeezing ground, time dependent, convergence
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