The geomechanical modeling of failure and post-failure stages of rainfall-induced shallow landslides represents a fundamental issue to properly assess the failure conditions and recognize the potential for long travel distances of the failed soil masses. Considering that these phenomena are among the most catastrophic natural hazard, as a contribution to the topic, the paper discusses the potentialities of a hydro-mechanical coupled FEM model to analyze the post-failure stage using an advanced constitutive model. Particularly, simple undrained triaxial tests and experimental evidences of centrifuge tests are reproduced firstly, for both cases of loose and dense soils. Then, two slope scale benchmarks are analyzed in the cases of vertical downward or horizontal water seepage and for both loose and dense soils. Compared with results obtained through standard limit equilibrium analyses, coupled FEM model provides a new comprehensive framework for failure and post-failure scenarios which includes a significant reduction of mean effective stresses also in the case of a loose soil slope subjected to vertical downward water seepage. The obtained results are particularly encouraging since they outline the possibility to analyse in a unique framework both the failure and post-failure stages. Moreover, the numerical analyses indicate that the post-failure mechanisms are intimately tied to specific predisposing factors and boundary conditions, rather than to a single mechanical or state parameter of soil, such as for instance the soil relative density.

Modelling the post-failure stage of rainfall-induced landslides of the flow-type.

CASCINI, Leonardo;CUOMO, SABATINO;
2013

Abstract

The geomechanical modeling of failure and post-failure stages of rainfall-induced shallow landslides represents a fundamental issue to properly assess the failure conditions and recognize the potential for long travel distances of the failed soil masses. Considering that these phenomena are among the most catastrophic natural hazard, as a contribution to the topic, the paper discusses the potentialities of a hydro-mechanical coupled FEM model to analyze the post-failure stage using an advanced constitutive model. Particularly, simple undrained triaxial tests and experimental evidences of centrifuge tests are reproduced firstly, for both cases of loose and dense soils. Then, two slope scale benchmarks are analyzed in the cases of vertical downward or horizontal water seepage and for both loose and dense soils. Compared with results obtained through standard limit equilibrium analyses, coupled FEM model provides a new comprehensive framework for failure and post-failure scenarios which includes a significant reduction of mean effective stresses also in the case of a loose soil slope subjected to vertical downward water seepage. The obtained results are particularly encouraging since they outline the possibility to analyse in a unique framework both the failure and post-failure stages. Moreover, the numerical analyses indicate that the post-failure mechanisms are intimately tied to specific predisposing factors and boundary conditions, rather than to a single mechanical or state parameter of soil, such as for instance the soil relative density.
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/11386/3993055
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 46
  • ???jsp.display-item.citation.isi??? 46
social impact