Varden, RP & Woods, MJ 2015, 'Design approach for squeezing ground', in Y Potvin (ed.), Proceedings of the International Seminar on Design Methods in Underground Mining
, Australian Centre for Geomechanics, Perth, pp. 489-504, https://doi.org/10.36487/ACG_rep/1511_30_Varden
Many mines experience squeezing ground conditions due to orebodies located in weak rock masses. Often, the conditions leading to squeezing ground are not recognised or underestimated at the feasibility stage, leading to significant difficulties in mining the deposit, high costs and lost resources. There are a number of processes to determine the potential existence and degree of squeezing ground. Feasibility study to determine the rock mass behaviour will significantly reduce the risks associated with mining such deposits. In many cases, it is not possible to prevent squeezing occurring; however, good planning at the feasibility stage can provide the means to control the ground to allow economical extraction.
The aim of this paper is to present an approach to maintain access development in squeezing ground identified during the feasibility study. Much is written about squeezing ground, but mainly about how to solve a problem that has already occurred (Potvin & Hadjigeorgiou 2008; Sandy et al. 2007). The aim of this paper is to give guidance for planning and management solutions for a deposit that will likely encounter squeezing ground conditions. The paper will also discuss operational requirements that need to be considered at the preproduction stage.
The paper reviews ground control schemes aimed at controlling movement before and during stoping. It is based on experiences and research conducted at mines experiencing squeezing ground conditions and reviews considerations in design and monitoring to mitigate outcomes associated with squeezing rock masses.
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