Experimental evaluation of dynamic geotechnical parameters of tailings

Abstract

The paper is focused on the testing of material from the "Lyulyakovitsa" tailings dam situated in proximity to the town of Panagyurishte in Bulgaria. The primary objective of this study is to investigate various laboratory techniques aimed at determining essential dynamic characteristics of the studied material. This research is conducted with the goal of subsequently assessing the seismic response of the existing tailings dam. In the context of performing an equivalent linear analysis, a widely used approach in geotechnical earthquake engineering, several crucial relationships and parameters come into play. These include the material's stiffness degradation, the damping ratio, and the small-strain stiffness, expressed through the shear wave velocity. The paper describes analysis of three experiments carried out in the geotechnical laboratory "Komaba" at the University of Tokyo. These experiments introduce undrained cyclic triaxial tests conducted under identical relative density (95%) of the tailings and executed at 50 kPa, 80 kPa, and 100 kPa effective confining stress, specifically, respectively. Additionally, two distinct testing methods were employed to measure the shear wave velocity in the specimens. The findings align with certain established directions in the existing literature for characterizing the dynamic properties of granular soils. Simultaneously, they underscore the practicality of the laboratory experiments adopted for acquiring a comprehensive set of relationships and parameters.