Performance of a reinforced embankment on a sensitive Champlain clay deposit

Abstract

An existing elastoviscoplastic constitutive model is modified using concepts of the state-dependent fluidity parameters and the damage law, to incorporate the effect of soil structure and its destructuration. The model is employed to simulate the performance of a well-documented case study of the reinforced test embankment constructed over a sensitive Champlain clay deposit at Saint Alban, Quebec. The finite element calculations, using both the original (nonstructured) and modified (structured) elastoviscoplastic soil models, are compared with the observed field data from a test embankment brought to failure. The results from the structured elastoviscoplastic soil model show better agreements with the field data when compared with those analyzed using the nonstructured elastoviscoplastic soil model. The modified model captures many features of the reinforced embankment behaviour, such as vertical settlement, excess pore-water pressure responses, and reinforcement force. However, they also reveal the fact that another important characteristic of the natural clay deposit -anisotropy -needs to be considered to provide an adequate prediction of horizontal deformations. The role of geosynthetic reinforcement and its viscosity on short-term responses of the reinforced embankment examined in this study is also discussed embankments observed behaviour such as vertical settlement, excess pore water pressure response and reinforcement force. However, the horizontal deformations in the clay deposit were not modeled satisfactorily. The role of geosynthetic reinforcement and its viscosity on the shortterm response of the reinforced embankment is also discussed

A pressuremeter-based evaluation of structure in London Clay using a kinematic hardening constitutive model

“…It was shown that the initial structure strongly affected some important simulation outcomes such as tunnel lining loads and embankment failure height. The relevance of the initial structure has been confirmed by other researchers using analogous formulations [59].…”

Long-term reinforcement strains for column supported embankments with viscous reinforcement by FEM

“…The uniaxial formulation of a multi-Kelvin model proposed by Zhang and Moore (1997a) has been used to successfully capture reinforcement viscosity in reinforced embankments without columns (e.g., Rowe, 2001, 2008;Rowe and Taechakumthorn, 2011;Karim et al, 2012;Taechakumthorn and Rowe, 2012a, 2012c. The reinforcement constitutive model in the present study is based on a 3D formulation of nonlinear viscoelastic model proposed by Zhang and Moore (1997b), which was extended from their uniaxial multi-Kelvin version (Zhang and Moore, 1997a).…”

“…Some researchers (e.g., Rowe, 2001, 2008;Rowe and Taechakumthorn, 2011;Karim et al, 2012;Taechakumthorn and Rowe, 2012a, 2012c have demonstrated that reinforcement viscosity is of importance to the interpretation of timedependent behaviour of basally reinforced embankments without columns. Also, a few recent studies (e.g., Ariyarathne et al, 2013;Rowe, 2015a, 2016) have shown that it is necessary to consider the viscous nature of reinforcement for reinforced embankment supported by rigid piles and or semi-rigid DMM columns.…”

Field Test Study on a Short Pile - net Composite Foundation over Gravel Clay for High - Speed Railways

“…With technical improvement, the pile-net composite foundation has been extensively applied in reinforcing the soft soil foundation of high-speed railways [3]. The pile-net composite foundation mainly consists of six parts [4]: the upper embankment fill, the grid network, the sand-gravel cushion, the reinforced area in the pile-soil composite region, the pile-soil underlying soft soil layer, and the bearing layer. Unlike in single composite foundations [5], the net and the soil work together to share the upper load in pile-net composite foundations [6].…”