Ground support

From Queen's University Mine Design Wiki

This article is about the application of ground support strategies and techniques to "underground mining projects". For the article on general geotechnical design see Geotechnical Design.

Ground support is a set of techniques, elements and methods that enable the conservation or mobilization of a rockmass' initial strength. The rockmass is given the ability to self-support throughout the course of mining. The ultimate goal of this practice is to allow for mining to occur safely while maintaining the stability of created underground excavations.These techniques can be divided into two main categories .

Support techniques refer to the action of applying an external reactive force to a rock surface in the process of deformation, i.e. submitted to strain causing changes in the shape, size and volume of the rock . Reinforcement techniques refer to the action of adding internal support, e.g. rockbolts, to maintain or improve the rockmass' properties prior to deformation. 

See Main Article: The information required for the mine design

Significant Properties of Support Elements

Uses of Ground Support

Historically, the installation of ground support was confined to temporary or permanent excavations.

Miner in Lynch, Kentucky. U.S. Steel (1950)

Temporary excavations such as small and narrow shrinkage mining stopes, see article on Mining Methods would have been supported with long timber members to prevent ground failures in these workings. These workings would typically have remained opened for short periods of time (1-2 weeks). As for permanent excavations such as shaft stations which can remain opened for years, permanent support and reinforcement was installed. Often times, the temporary support previously put in place was removed and replaced with more permanent forms. This is contrary to modern practice where the rock-support interactions are an important design consideration.

Active vs. Passive

Primary vs. Secondary

Empirical Support Design

The appropriate ground support strategies are selected through various engineering design techniques. In Ontario, this design selection is governed by legal requirements defined in the Ontario Occupational Health and Safety Act.

External Sources

http://en.wikipedia.org/wiki/Wikipedia:Citing_sources