Acid mine drainage erosion and earthquake coupling action to slope in rich sulfide open pit

Abstract

The coupling action by Acid Mine Drainage erosion and earthquake is one of the major inducements of slope instability in chemical (metal) mine. The tests shown that the affected distance by AMD erosion is about 60-100m to slope inner in general; The natural frequency in slope area is small under the influence of steps free face; in earthquake field, the natural frequency of shear stress at fault section is obviously higher than other sections, high stress area mostly distributes at the bottom of slope and fault section; The stress is parallel to the dominant joints direction at the free face of steps; under the coupling action of AMD and earthquake, enrichment area of high stress comes up nearby the free face of the slope; Stress enrichment area of AMD erosion is enlarged, while strength is enhanced, and the crest value of displacement change is increased by 10% comparing with single earthquake stress filed. The sections are ranked from the greater to smaller one based on crest value of displacement inner the slope: the fault section, the centre of slope, the top of steps, and the footing of the slope. © 2008 Science Press Beijing and Springer-Verlag GmbH Berlin Heidelberg Geotechnical Engineering for Disaster Mitigation and Rehabilitation.