Paper contribution

Uniaxial compressive strength and durability of sandstones and marls with varying moisture content

Sanja Dugonjić Jovančević; Martina Vivoda Prodan; Josip Peranić; Igor Ružić

Proceedings
EUROCK 2026
Pages
309-314
Submitted
28 January 2026
Accepted
15 June 2026
Published
12 August 2026

Summary

Abstract

The compressive strength of sedimentary rocks varies significantly with moisture content. In this study, Point Load Tests (PLT) and corresponding Uniaxial Compressive Strength (UCS) correlations were determined for marl and sandstone samples with varying water contents, tested in two pilot areas in the northern Adriatic. The specimens were collected from the coastal zone where cyclic wetting and drying occurs, influencing the mechanical stability of the rock mass. Samples were tested in their in situ condition, after 24 hours, and after one week of wetting. PLT on irregular samples and Slake Durability Test were performed in the Geotechnical Laboratory at the Faculty of Civil Engineering, University of Rijeka following the standardized procedures. Marls testing results indicate a clear reduction in UCS with increasing water content, while Slake Durability Tests revealed high resistance to low disintegration of marls under cyclic environmental conditions. On the other hand, sandstone samples have shown varying behaviour, depending on the period of sampling, initial water content and moisture penetration regimes. The results indicate that the mechanical properties of the rock mass are significantly affected by its heterogeneity and the environmental conditions in which it occurs. Furthermore, they emphasize the need to account for additional controlling factors to improve the interpretation of index test results and to validate the mechanical behaviour of surface materials exposed to marine environmental conditions.

Contributors

Authors

  1. Sanja Dugonjić Jovančević University of Rijeka, Faculty of Civil Engineering, Croatia ORCID 0000-0002-0242-7409
  2. Martina Vivoda Prodan University of Rijeka, Faculty of Civil Engineering, Croatia ORCID 0000-0003-0464-2687
  3. Josip Peranić University of Rijeka, Faculty of Civil Engineering, Croatia ORCID 0000-0002-2574-6349
  4. Igor Ružić University of Rijeka, Faculty of Civil Engineering, Croatia

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References

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