Paper contribution

Physical – mechanical properties of the rocks from Kuklici natural heritage site

Miloš Marjanović; Ivica Milevski; Branislav Sretković; Aleksandra Nikolovska Atanasovska; Uroš Đurić; Igor Pesevski

Proceedings
EUROCK 2026
Pages
1257-1263
Submitted
28 January 2026
Accepted
15 June 2026
Published
12 August 2026

Summary

Abstract

The Kuklici site near Kratovo, R.N. Macedonia, represents a geomorphologically unique area characterized by a dense concentration of naturally formed erosional columns and rock pillars locally referred to as “stone dolls.” The site provides an excellent natural laboratory for studying the mechanical behavior and weathering susceptibility of volcaniclastic and pyroclastic rocks exposed to long-term atmospheric and surface processes. This study presents the results of a preliminary field and laboratory investigations aimed at characterizing the physical-mechanical properties of the rocks form the Kuklici formations. Non-invasive needle penetration tests and Schmidt’s hammer tests were performed to assess the surface hardness and relative resistance to mechanical disintegration of exposed rock masses. Representative samples were collected for laboratory testing, including point load index, slake durability, and specific and unit weight determinations, to evaluate the intrinsic strength and durability of the materials under cyclic wetting and drying conditions. The obtained results are discussed and compared with literature results for similar rock formations from throughout the World. This research contributes to the ongoing DEMONITOR project, within which LiDAR surveys, photogrammetric analyses, and geophysical investigations will be integrated to develop a comprehensive model for monitoring and predicting erosion processes affecting natural heritage sites composed of weak volcanic rocks.

Contributors

Authors

  1. Miloš Marjanović University of Belgrade Faculty of Mining and Geology ORCID 0000-0002-9675-1401
  2. Ivica Milevski Saints Cyril and Methodius University of Skopje Faculty of Natural Science and Mathematics
  3. Branislav Sretković University of Belgrade Faculty of Mining and Geology
  4. Aleksandra Nikolovska Atanasovska Saints Cyril and Methodius University in Skopje Faculty of Civil Engineering
  5. Uroš Đurić University of Belgrade Faculty of Civil Engineering
  6. Igor Pesevski Saints Cyril and Methodius University in Skopje Faculty of Civil Engineering ORCID 0000-0002-2748-5795

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