Paper contribution

Changes of geomechanical state around reconstructed underground roadways in the historical salt mine

Zbigniew Niedbalski; Piotr Małkowski; Łukasz Bednarek

Proceedings
EUROCK 2026
Pages
1225-1230
Submitted
28 January 2026
Accepted
15 June 2026
Published
12 August 2026

Summary

Abstract

Underground salt mines in Poland have existed continuously since 13th century. Two of them are preserved as museums, were inscribed on UNESCO heritage list in 1978 and 2013. The underground chambers open to tourists were usually excavated 100–400 years ago. In this long period of time the secondary state around roadways was established but salt, as a rheological material, still deforms, which forces the periodic rebuilding of chambers and corridors. Sometimes, excavations need to be reconstructed for other reasons, e.g., changes in technical equipment, their adjustment to current safety requirements, or support repairs. These works generally lead to an increase in roadway cross-sections and to changes in the geomechanical conditions around the workings. Since underground excavations have variable cross-sections, ranging from a few to more than a hundred square meters, all mining works require individual stability analyses.               The analysis of reconstructed underground excavations in one of these historical salt mines was presented in the paper. The analysed chamber and roadways were mined at depths of 180-210 m in the 1st half of 18th century. They need to be rebuilt and widened, because mine manager plans to increase the number of visitors in the mine. The inventory of chambers and roadways, laboratory tests on salt geomechanical parameters, ground monitoring and 2D numerical modelling were carried out to determine the state of stress and the extend of the plastic zone before and after rebuilding. The conducted investigations should enable safe mining operations and ensure the long-term stability of the historical structures in this part of the mine.

Contributors

Authors

  1. Zbigniew Niedbalski AGH University of Krakow, Poland ORCID 0000-0003-0497-0162
  2. Piotr Małkowski AGH University of Krakow, Poland ORCID 0009-0008-0843-7174
  3. Łukasz Bednarek AGH University of Krakow, Poland ORCID 0000-0002-8239-5864

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References

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