The Development of Rock Engineering in South Africa
[ Nielen van der Merwe ] - Department of Mining Engineering, University of Pretoria, Pretoria, South Africa
This paper is intended to place on record the development of rock engineering in South Africa to serve as an example and encouragement to other groups or countries where the same level of development has not yet been reached. In South Africa, the emphasis in rock engineering is on the mining industry, being the most important contributor to the national economy. The fortunes of rock engineering is thus linked to the well-being of the mining industry. The paper discusses the development of rock engineering in South Africa against the background of the history of the mining industry and political development of the country. The physical underground coal mining environment in South Africa is similar to
that in the USA and Australia. The depth of mining is typically 50 to 250 m and the mining height approximately 2 to 3 m. The seams are mostly flat or have small inclinations. By contrast, gold is mined at depths approaching 3 800 m below surface. The deposits are also tabular, ranging from as little as 0,8 m thick to over 2 m in a metamorphic rock environment, mostly quartzite. Rock temperatures are in the region of 50' C to 60' C. Virgin rock stress levels are in the range 75 MPa to 90 Mpa and can be concentrated several times by the creation of mining openings.
Platinum is mined in the intermediate depth range of 50 m to 1 000 m below surface. 'The rock environment is igneous. Other important minerals that are mined include dianionds, mostly contained in igneous pipes and mined by block caving methods, iron ore and other base metals.
The major mining activity is in coal, gold and platinnm.