Abstract:
Several high-impact tailings dam failures around the world in recent years have placed a renewed focus
on the stability of tailings dams and pointed to potential shortcomings in traditional drained design
and safety evaluation procedures. A need to consider undrained shear strength in the design of tailings
facilities has become apparent. However, there are specific requirements that need to be met before
undrained shearing occurs. In South Africa, the last major failure was likely the Merriespruit disaster in
1994, which leads to the question of whether the conditions required for undrained shearing are readily
applicable to South African tailings dams. This paper describes research at the University of Pretoria
that has recently commenced to further investigate the conditions required for undrained failure to
occur. The research includes laboratory and field testing to replicate these conditions in the laboratory
and relate them to those found in an active tailings dam.
