Paper contribution

Physical and analytical modelling of sliding-toppling combined slope failures

Sifan Yuan; Patricia Carracelas Lamela; Ignacio Pérez-Rey; Leandro R. Alejano

Proceedings
EUROCK 2026
Pages
415-420
Submitted
28 January 2026
Accepted
15 June 2026
Published
12 August 2026

Summary

Abstract

Simple failure mechanisms including planar, wedge, toppling and circular failure are typically analysed when studying rock slope stability. However, combined failure mechanisms sometimes take place making rock slopes unstable, so it is convenient to consider their possible occurrence. Despite this, research on combined mechanisms remains limited. Among potential combined failure mechanisms in rock masses reported in the literature, the coupling of sliding in the upper part of the slope and toppling in the front is a possible one. This mechanism has also been observed in masonry retaining walls, where the sliding failure of the backfill induces toppling of the drystone blocks. The main objective of this work is to investigate the stability and failure mechanisms of three different configurations representative of such structures, through an experimental program based on tilt-tests on physical models. The critical tilting angles obtained from the experiments are compared against analytical limit equilibrium estimates, showing good agreement. The slight differences in results observed stem from imperfect granite block cutting, limitations of the testing apparatus and inaccuracies derived from simplifying assumptions. Finally, tentative numerical models are presented, and their results show good agreement with the experimental and analytical ones. While each method has inherent strengths and limitations, their cross-validation offers a more robust analysis of failure mechanisms observed in retaining walls and rock slopes affected by combined failure mechanisms.

Contributors

Authors

  1. Sifan Yuan CINTECX, Universidade de Vigo, Grupo GESSMin, 36310, Vigo, Spain
  2. Patricia Carracelas Lamela CINTECX, Universidade de Vigo, Grupo GESSMin, 36310, Vigo, Spain
  3. Ignacio Pérez-Rey CINTECX, Universidade de Vigo, Grupo GESSMin, 36310, Vigo, Spain ORCID 0000-0003-0883-7211
  4. Leandro R. Alejano CINTECX, Universidade de Vigo, Grupo GESSMin, 36310, Vigo, Spain

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References

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