Paper contribution

Comparative assessment for prediction of settlements for piles in weak rocks: Case study

Sead Abazi; Spasen Gjorgjevski; Josif Josifovski; Bojan Susinov

Proceedings
EUROCK 2026
Pages
1461-1466
Submitted
28 January 2026
Accepted
15 June 2026
Published
12 August 2026

Summary

Abstract

This article aims to assess settlements and the load-bearing capacity of piles through experimental and numerical analyses in specific weak rock materials with pronounced anisotropy and heterogeneity. To this aim, extensive program of field tests was performed with a special static load test system for receiving load through the use of a specially designed platform that serves as a counter load with capacity up to 900 tones. The results from two case histories are presented. First case is related to bridges with large dimensions foundered in weak rock mass composed of schists formation present on sections at Macedonian highway section in phase of construction, while the second one is related to underground excavations in the urban area of the capital Skopje, where the structures are foundered in marls. From the analysis of a numerous experimental tests of piles to the designed or ultimate load, a classification of the load - settlement dependence was derived according to several parameters. The experimental sections were also analysed with numerical methods. Results indicate that the piles constructed in such weak rock mass media shows that the limit state of failure is not reached for the maximum applied designed loads. Findings from the applied approach are used for preparation of interaction schemes, where the influential parameters of the natural structure - the terrain and the artificial construction - the structure are connected. As a result of the analyses, a large number of correlations between the examined parameters were established, and findings from all analyses are used to establish some correlations between settlements and rock mass quality defined by some known rock mass systems as GSI and Q. Some ideas for further development of the methodology are underlined.

Contributors

Authors

  1. Sead Abazi Faculty of Civil Engineering -Skopje, North Macedonia, Republic of ORCID 0000-0001-8263-600X
  2. Spasen Gjorgjevski Faculty of Civil Engineering -Skopje, North Macedonia, Republic of
  3. Josif Josifovski Faculty of Civil Engineering -Skopje, North Macedonia, Republic of ORCID 0000-0001-9771-8331
  4. Bojan Susinov Faculty of Civil Engineering -Skopje, North Macedonia, Republic of ORCID 0000-0002-9306-4171

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References

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