Warning Signs to Geotechnical Failure of Mining Structures

Abstract

Mining structures, such as open pits and underground mines, tailings dams and waste rock dumps, under stress can suffer geotechnical damage and fail. Studies were carried out on large scale failures in a form of rock mass collapse (collapse of an open pit slope and a surface crown pillar), seismic events (rockburst and gas outbursts), mine inundation, and waste rock material instability (tailings dams and waste rock dumps). The case studies revealed that geotechnical failure of mining structures were preceded by warning signs like indicators and precursors and that the failures were triggered by external factors like rainfalls or mine blasting. For large scale geotechnical failures, the initial precursors were present months or even years before failure. During the period from the initiation of structural damage to the final failure many various types of precursors were commonly reported and the number and scale of precursors increased towards impending failure. In a number of cases it was found that large scale geotechnical failures were preceded by a succession of small scale failures.