Design for upgrading of tailing dam Toranica - Kriva Palanka in complex geotechnical and hydrological conditions

摘要

This paper deals with stress-strain and stability analysis of tailing dam Toranica - Kriva Palanka for specific stages of construction. In the technological concept of the mine for lead and zinc Toranica - Kriva Palanka (north-east of Republic of Macedonia), a tailing dam for disposal of flotation barren soil which remains after the processing of the mine material had been constructed. This tailing dam exists in the past 20 years. On the upstream side there is an earthfill retention dam for diversion of river Kriva Reka into drainage tunnel. The tailing dam is on the down stream side made by fine sand and silt as products of flotation process. The works in the mine Toranica had been stopped for some years. Stress-strain and stability analysis has been made for the existing conditions of the tailing dam and for the design conditions with upgrading of the tailing dam. The crucial parameter was defining of the need of the drainage blanket to the toe of the down stream slope of tailing dam. The calculations have been carried out by finite element method using geotechnical software package PLAXIS and by limit equilibrium method using software package GGU Stability.