Influence of degradation of structure on the behaviour of a full-scale embankment

The advanced constitutive model KHSM for structured clays, which incorporates the effects of loss of structure within an elastoplastic framework, has been implemented in a finite element procedure and used to investigate the failure height and pore-water pressures of embankment A constructed at Saint Alban, Quebec. For the purpose of model comparison, simulations were also performed using the standard bubble model (KHM) without destructuration. The numerical predictions of pore-water pressures and settlements are also compared with field measurements. The results clearly demonstrate the importance of including the effects of loss of structure in the analysis. Key words: structured clays, constitutive models, numerical analysis, embankments, full-scale tests, failure. Le modele constitutif avance pour les argiles structurees KHSM, qui integre les effets de la perte de structure dans un cadre elasto-plastique, a ete implante dans une procedure par elements finis et utilise pour etudier la hauteur de rupture et les pressions interstitielles du talus A, construite a Saint-Alban, Quebec. Afin de comparer les modeles, des simulations ont aussi ete realisees avec le modele de bulle standard (KHM) sans destructuration. De plus, les predictions numeriques de pression interstitielle et de tassement ont ete comparees avec les mesures prises sur le terrain. Les resultats demontrent clairement l'importance d'inclure les effets de la perte de structure lors de l'analyse. Mots-cles : argiles structurees, modeles constitutifs, analyse numerique, talus, essai a grande echelle, rupture. [Traduit par la Redaction]
Introduction Design and construction of engineered structures on soft soils is becoming more commonplace because of the lack of better land available for construction in both developed and developing regions [...]