Materiały konferencyjne SEP 1993 - tom 2

Underground Exploitation School '93 CURRENT ROCK ENGINEERING RESEARCH: •PROBLEMS: - Averag6 in last years about 55 per cent of all fatalitłes were rock related. Of these 52 per cent were attributed to rockbursts. - A further issue is the losses causod by rockbursts increased significantly with depth. - From an economic standpolnt, it is estmated that 4 per cent of panel shifts are lost in gold mines as a result of rockbursts and rockfalls. This increases stOf »ng costs by about 5 per cent amounting to hundreds of millions of rands per annum. Other significant losses suffered by the mines is due to dilution caused by rockfalls and rockbursts. It has been estimated that a reduction in stoping width of an achievable 8 per cent would increase annual working profit from gold by 19 per cent. •STRATEGIES TO OVERCOME THESE PROBLEMS: Better layout design criteria. - Design of improved support systems. - Methods for anticipating or pre-empting damaging seismic actłvity. 118 Tom II