3D Numerical modeling of Soft soil Improved by Rigid Inclusions Supported an Embankment

Salah, MESSIOUD; Yassamina, NEGHMOUCHE

doi:10.30684/etj.2021.132023.1083

	3D Numerical modeling of Soft soil Improved by Rigid Inclusions Supported an Embankment
Engineering and Technology Journal
Article 2, Volume 40, Issue 5, 2022, Pages 636-648 PDF (1.1 M)
Document Type: Research Paper
DOI: 10.30684/etj.2021.132023.1083
Authors
MESSIOUD Salah^* ¹; NEGHMOUCHE Yassamina²
¹LGCE, Universit&eacute; Mohammed Seddik Benyahia BP 98 Ouled aissa
²LGCE, Université Mohammed Seddik Benyahia BP 98 Ouled aissa
Abstract
Abstract A three-dimensional finite element model suggested to determine the settlements and stresses of an embankment placed on soft soil reinforced by rigid inclusions. To make it simple the layers of soil and the embankment are supposed to be horizontal in a semi-infinite medium and the base of the soft soil is supposed to be rigid (bedrock). The interacting elements of the model are supposed to be elastic. The determination of the behavior of the soil-inclusions-embankment system was realized according to the construction phases of the embankment layers. The settlements and stresses were calculated according to construction phases of the embankment layers. At the end of each calculation phase, the stress field and the displacement field are extracted. The values are then introduced into the model the beginning of the next phase. The obtained results are presented in terms of the (settlement) vertical displacements and vertical stresses for the elementary cell and the global model respectively. This study allows the observation of three-dimensional interactions; the mechanisms of load transfer and the interaction between the different zones of the embankment. The numerical calculations are much lower than those measured in situ. A verification calculation on the stresses transmitted by the rigid inclusion shows that only 90% of the total load is applied with the numerical calculation.
Highlights
Numerical modeling of soft soil reinforced by rigid inclusions. Calculation of settlements and stresses under the placement of embankment layers The settlement at the embankment soil interface has been reduced by 90% compared to a soil without reinforcement. Despite the problems encountered with elastoplastic calculations, a good distribution of the stresses in the inclusions is obtained. The charge transfer mechanism is well done for the elementary cell.
Keywords
Finite Elements,,; ,،,؛Rigid Inclusions,,; ,،,؛Soft Soil,,; ,،,؛Settlement,,; ,،,؛Embankment

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