Abstract
Geotechnical and geophysical methods used for site characterization, as well as instrumentation for geotechnical monitoring, have advanced enormously in recent decades. As a consequence, a deeper understanding of the mechanical and physical properties of natural deposits, including their spatial variability in situ, is now possible. Modern monitoring systems allow the observational method to be applied to a greater range of situations with increasing confidence.
The combined use of modern soil mechanics and the observational method often represent the only viable option for tackling the challenges posed by large or unusual structures in difficult geological and geotechnical environments. This is particularly the case when the duration of the project allows one to maximise the benefits of applying the observational method. The lecture will illustrate this with reference to the long-term project at Zelazny Most, Poland, the largest tailings storage facility in Europe and one of the largest of its kind in the world.
Construction of the Zelazny Most tailings dam commenced in 1977 and up to 2012, 506 million cubic metres of tailings have been stored. The 14.3 km long ring-dam has reached heights of between 31 and 60 m and current plans are to raise it by a further 15 m. Significant geotechnical hazards have been identified about 20 years ago and now two dam sections are being monitored. The monitoring has showed the commencement of horizontal displacements along deep shear planes which are a result of glacio-tectonic phenomena during three major periods of glaciation. These displacements are continuing and are of great concern to all involved in the project.
- Advance booking for lecture not required
- Tea and biscuits will be available at 5.00pm – 5.30pm.