Paper contribution

Assessing the unconfined compressive strength of limestones using indirect testing methods

Nino Salčin; Miloš Marjanović

Proceedings
EUROCK 2026
Pages
511-515
Submitted
28 January 2026
Accepted
15 June 2026
Published
12 August 2026

Summary

Abstract

The unconfined compressive strength of rocks is a key design parameter, but its reliable determination remains a challenge due to the heterogeneity, cracking, and anisotropy of rock materials. Standard laboratory testing of uniaxial compressive strength gives the most accurate results, but is challenging, expensive, and often limited by sample quality and availability. Therefore, indirect methods are widely used in practice. This paper presents research conducted on limestones from the territory of Belgrade to determine the correlations between compressive strengths obtained using different indirect testing methods. A total of 156 samples were tested, on which needle penetration tests, Schmidt hammer tests, and point load tests were conducted. In contrast, an unconfined compression test was performed on a few samples to validate the best correlations. Thirty existing correlations across different tests and lithologies were considered, and based on the results, recommendations were given on which correlations are most suitable for the Belgrade Sarmatian limestones and which tests should be relied on more, depending on the sample's strength.

Contributors

Authors

  1. Nino Salčin Hidrozavod DTD, Novi Sad, Serbia ORCID 0009-0002-3884-616X
  2. Miloš Marjanović Faculty of Mining and Geology, Belgrade, Serbia ORCID 0000-0002-9675-1401

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