Article

Numerical simulations of stone column installation

Canadian Geotechnical Journal (Impact Factor: 1.21). 09/2010; 47(10):1127-1138. DOI: 10.1139/T10-019

ABSTRACT Cet article decrit les resultats de simulations numeriques visant a investiguer les effets de l'installation de colonnes ballastees dans de l'argile molle naturelle. La geometrie du probleme est simplifiee sous forme de symetrie axiale, en considerant l'installation d'une seule colonne. L'installation de la colonne ballastee est modelisee en tant qu'une expansion non-drainee d'une cavite cylindrique, ainsi la pression interstitielle excessive generee est dissipee vers la colonne permeable. Le processus est simule a l'aide d'un code par elements finis qui permet les grands deplacements. Les proprietes de l'argile molle correspondent a l'argile Bothkennar, qui est modelisee avec S-CLAY1 et S-CLAY1S, qui eux sont des modeles de type Cam-clay considerant l'anisotropie et la destructuration. L'installation des colonnes ballastees altere le sol environnant. L'expansion de la cavite genere des pressions interstitielles excessives, augmente les contraintes horizontales sur le sol, et modifie de facon importante la structure du sol. Les simulations numeriques effectuees ont permis d'evaluer la valeur du coefficient de pression laterale des terres post-installations ainsi que les variations dans la structure du sol causees par l'installation des colonnes. Ces effets et leur influence sur la conception des colonnes ballastees sont discutes.

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