Dam stability: How to verify the actual stability?
2016 (English)Conference paper, Presentation (Refereed)
Mining operations produce huge volumes of waste products. Tailings, the fine grained waste material, is often managed in tailings management facilities (TMFs) surrounded by dam structures, i.e. tailings dams. Stability of tailings dams, amongst other things, is an in-creasing concern as tailings dams continue to fail. There is not just one single reason why dam failures occur. Dam stability is, however, one of the keystones required for good tailings management and good tailings dam safety. Dam stability can be divided into two main parts: a) stability analysis and b) surveillance and monitoring. The first is carried out at the initial design (normally by consultants) and is thereafter updated during operation of the TMF. A commonly used method for the analysis is the limit equilibrium method (LE). Here a factor of safety (FS) is calculated and in Sweden this is normally 1,5. In order to verify the behavior of the dam surveillance and monitoring is used. Typically pore pressures, horizontal and vertical movements and seepage are monitored in order to find changes in the trend of readings or to identify unexpected behavior. There is, however, no way of linking the readings to the stability analysis as the LE analyses are based on analysis of the conditions at failure. Thus it is not possible to describe the behavior of the dam before failure and the monitoring cannot be used to “give” warning signals before failure. This paper describes a case study where advanced numerical modelling, have been used to determine deformations in the dam structure, which have been verified by inclinometer readings. It has been possible to verify the actual stability for the dam as it has been possible to link in-situ readings to the model. The concept described is not only applicable to tailings dams, but can also be used for any type of dam.
Place, publisher, year, edition, pages
tailings, dams, simulations, Factor of Safety, Civil engineering and architecture - Geoengineering and mining engineering
Samhällsbyggnadsteknik och arkitektur - Geoteknik och gruvteknik
Research subject Soil Mechanics
IdentifiersURN: urn:nbn:se:ltu:diva-39636Local ID: e76dbace-ec6c-464a-bc40-a7b16dd688f5OAI: oai:DiVA.org:ltu-39636DiVA: diva2:1013152
Tailings and Mine Waste 2016 : 02/10/2016 - 05/10/2016
Godkänd; 2016; 20160608 (svek)2016-10-032016-10-03Bibliographically approved