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More and more underground mines are experiencing rockburst, which is a stress-induced violent ejection of rock that is normally encountered in deep mines. There are different approaches to determine the energy from rockburst, which is caused by excess stress concentrations in the rock mass. A major engineering challenge for mines experiencing this significant seismicity is to design the dynamic performance of their support systems. Therefore, a retaining system using dynamic rockbolts in combination with high-tensile steel wire mesh was tested to ascertain the behaviour and quantify the suitability of the system. A special large scale test facility was constructed for the purpose, which allowed verification of the percentage of energy transmitted by the rockbolts and wire mesh, based on the input energy. Numerous tests were carried out providing first findings on the load distribution within the support system.

This paper presents the slope stability analysis for the current as well as projected (final) geometry of waste dump Sandstone Open Pit “Osielec”. For the stability analysis six sections were selected. Then, the final geometry of the waste dump was designed and the stability analysis was conducted. On the basis of the analysis results the opportunities to improve the stability of the object were identified. The next issue addressed in the paper was to determine the proportion of the mixture containing mining and processing wastes, for which the waste dump remains stable. Stability calculations were carried out using Janbu method, which belongs to the limit equilibrium methods.

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The extraction of the Bełchatów lignite deposit located in the vicinity of the Dębina salt dome requires careful planning that considers the influence of mining projects on the slope and salt dome stability conditions. The instability problem is directly related to horizontal and vertical displacement, as well as the complex geological and mining conditions. These conditions are very unique with regard to the co-occurrence of the salt dome and lignite deposits in the same area, as well as the large scale of the pit wall slope. Thus, predicting rock mass behavior and ensuring the safety of mining operations are important issues. The presented analysis focused on the influence of long-term lignite extraction on the western pit wall slope of the Bełchatów field and the salt dome’s stability conditions. This study offers a comprehensive approach to a complex geotechnical problem defined by large-scale, complex geometry, and geological conditions. The rock mass behavior and stress conditions are simulated in numerical modelling. The results of the presented analysis will be useful not only for present mining activities but also for future developments related to post-mining and recultivation plans.