Paper contribution

Stability assessment of quarry slopes through laboratory tests and numerical modelling

Laura Turbessi; Chiara Caselle; Gessica Umili; Anna Maria Ferrero

Proceedings
EUROCK 2026
Pages
1429-1434
Submitted
28 January 2026
Accepted
15 June 2026
Published
12 August 2026

Summary

Abstract

This paper presents a study carried out in a Serizzo di Antigorio quarry in the Upper Formazza Valley (Premia-VB, northwestern Italy), where the sliding of a rock wedge in September 2023 caused injury to a worker. This fact highlighted the need for an in-depth assessment of the quarry stability. The objective of the study was to analyse the stability conditions of both active and inactive quarry faces through the integration of field surveys, laboratory tests, and numerical modelling. In particular, laboratory tests performed on representative rock samples included triaxial compression, uniaxial compression and indirect tensile strength tests. At the same time, field and remote surveys provided geometric and structural constraints for the digital reconstruction of the rock mass structure. Stability analyses were initially performed using Limit Equilibrium Method (LEM) codes to estimate safety factors and perform sensitivity analyses. 3D Distinct Element Method (DEM) simulations were subsequently run to investigate stress distribution within complex rock mass geometries. The numerical approach allowed for the identification of areas characterized by high stress concentrations and supported the design of a controlled blasting plan aimed at the safe removal of unstable rock volumes. The case study highlights the role of numerical models as fundamental tools to support traditional stability assessments, whose reliability is grounded in the geomechanical parameters determined through laboratory testing. These models provide detailed insights into the stress–strain behaviour and potential failure mechanisms, which are difficult to identify using conventional methods alone. The results demonstrate the effectiveness of an integrated approach, combining surveys, experimental testing, and numerical simulations, in managing risk in Alpine quarrying contexts.

Contributors

Authors

  1. Laura Turbessi Università di Torino, Italy ORCID 0009-0006-6257-970X
  2. Chiara Caselle Università di Torino, Italy
  3. Gessica Umili Università di Torino, Italy
  4. Anna Maria Ferrero Università di Torino, Italy

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References

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