The hydraulic fill method of erecting dams was characterized. The main assumptions and practical aspects of sand spigot were discussed on the example of the spigot of the dam body of the Zelazny Most Tailings Storage Facility (TSF). The advantages and disadvantages of the method are discussed, and the directions of attempts to implement pipelines rising along with sedimenting waste are presented, which are to reduce earthworks.

In this paper, existing knowledge on the behaviour of soil-steel composite structures (SSCSs) has been reviewed. In particular, the response of buried corrugated steel plates (CSPs) to static, semistatic, and dynamic loads has been covered. Furthermore, the performance of SSCS under extreme loading, i.e., loading until failure, has been studied. To investigate the behaviour of the type of composite structures considered, numerous full-scale tests and numerical simulations have been conducted for both arched and box shapes of the shell. In addition, researchers have examined different span lengths and cover depths. Furthermore, to enhance the load-bearing capacity of the composite structures, various stiffening elements have been applied and tested. The reviewshows that the mechanical features of SSCSs are mainly based on the interaction of the shell with the soil backfill. The structures, as a composite system, become appropriately stiff when completely backfilled. For this reason, the construction phase corresponds to the highest values of shell displacement and stress. Moreover, the method of laying and compacting the backfill, as well as the thickness of the cover, has a significant impact on the behaviour of the structure at the stage of operation in both the quantitative and qualitative sense. Finally, a limited number of studies are conducted on the ultimate bearing capacity of large-span SSCS and various reinforcing methods. Considerably more works will need to be done on this topic. It applies to both full scale tests and numerical analysis.

The paper presents the approach for optimization of preventive/technological measures increasing the safety of tailings pond dams. It is based on the combined use of monitoring results as well as advanced 3D finite element (FE) modeling. Under consideration was the eastern dam of Zelazny Most Tailings Storage Facility (TSF). As part of the work, four numerical models of the dam and the subsoil, differing in the spatial arrangement of the soil layers, were created. For this purpose, the kriging technique was used. The numerical models were calibrated against the measurements from the monitoring system. In particular the readings acquired from benchmarks, piezometers and inclinometers were used. The optimization of preventive measures was performed for the model that showed the best general fit to the monitoring data. The spatial distribution and installation time of relief wells were both optimized. It was shown that the optimized system of relief wells provides the required safety margin.