Repositório Comunidade: CEC-GEO
https://hdl.handle.net/1822/1092
CEC-GEO2024-03-28T19:56:50ZPrise en compte de la non saturation pour le dimensionnement des couches de chaussées
https://hdl.handle.net/1822/17064
Título: Prise en compte de la non saturation pour le dimensionnement des couches de chaussées
Autor: Fleureau, Jean-Marie; Coronado, Octavio; Correia, A. Gomes
Resumo: L’article présente des résultats d’essais triaxiaux à chargement répété réalisés sur une grave non traitée à base de gneiss. Des mesures locales très précises des déformations longitudinales et transversales ont été faites sur les échantillons compactés, ainsi que des mesures de pression interstitielle négative (succion). Les résultats mettent en évidence l’évolution des déformations réversibles et permanentes pendant la phase de conditionnement des échantillons, et la variation du module réversible sécant et du coefficient de Poisson sécant avec les contraintes sur différents chemins de chargement. Une interprétation simplifiée en contraintes effectives de ces résultats est proposée, dans la perspective d’une analyse plus rationnelle du dimensionnement des couches de chaussée.
<b>Tipo</b>: conferencePaper2012-02-14T15:42:53ZStress-strain behaviour of compacted geomaterials for pavements
https://hdl.handle.net/1822/12912
Título: Stress-strain behaviour of compacted geomaterials for pavements
Autor: Correia, A. Gomes; Anh Dan, L.; Koseki, J.; Tatsuoka, F.
Resumo: This paper presents some new and significant aspects of pre-failure deformation characteristics, particularly stress-strain properties at
small strains, of crushed unbound granular materials used in pavement construction. The data was obtained from a series of precision
cyclic triaxial tests performed at the Institute of Industrial Science, University of Tokyo, using stress paths and strain levels
representatives of pavement field conditions. Based in this data, effects of stress state and strain level in Young’s modulus are
discussed to some depth.; Cet article présente des aspects nouveaux et significatifs des caractéristiques des geomatériaux, en particulier les propriétés contraintedéformation
en petites déformations des matériaux granulaires concassés non traités utilisés dans la construction routière. Les donnés
ont été obtenus par des essais triaxiaux cycliques de précision réalisés à l’ "Institute of Industrial Science, University of Tokyo", en
utilisant des chemins de contrainte et des niveaux de déformation représentatives dans les chaussées. Ces données ont permis de
mettre en évidence les effets de l’état de contrainte et du niveau de déformation dans le Module d’Young.
<b>Tipo</b>: conferencePaper2011-07-20T10:36:07ZSummary
https://hdl.handle.net/1822/12911
Título: Summary
Autor: Correia, A. Gomes; Homych, P.
Resumo: The purpose of this session is to present research results whose primary concern is with the behaviour of subgrade soils under repeated loading in the context of the role they play in pavement design.
The six papers assigned to this session contained three papers from the Science project and three from outside the Science project.
The objective of the Science papers deal with:
- Harmonization of a test procedure for triaxial testing of subgrade soils.
- Prediction of subgrade moisture conditions for purposes of pavement design.
- Resilient behaviour of soils.
The three other papers, outside the Science programme, presented:
- A study on the influence of the behaviour of a clay subgrade on the performance of a flexible pavement. (First paper - Nottingham University).
- A study on the cyclic behaviour of l’ Ennerie sand, a material used as subgrade soil at the full-scale, pavement test facility of the Laboratoire Central des Ponts et Chaussées, in Nantes. (Second paper - LCPC, LRCP SaintBrieuc).
- A study on the cyclic behaviour of in situ samples of various fine-grained subgrade soils. (Third paper - Swedish Road and Transport Research Institute).
Descrição: Introdução ao livro de actas "Flexible Pavements"
<b>Tipo</b>: conferenceEditorial2011-07-20T10:23:57ZGeneralised effective stress analysis of strength and small strains behaviour of a silty sand, from dry to saturated state
https://hdl.handle.net/1822/12734
Título: Generalised effective stress analysis of strength and small strains behaviour of a silty sand, from dry to saturated state
Autor: Fleureau, Jean-Marie; Hadiwardoyo, S.; Correia, A. Gomes
Resumo: Very small to large strains properties of a silty sand were measured at several water contents ranging from a few percents to saturation, using three triaxial devices with different types of transducers. In the analysis of the data, attention was focused on the influence of water content on the maximum (Young’s) modulus, the decay of modulus with strain, the effect of the confining stress, etc. Isotropic and triaxial tests, with measurement of negative pore water pressure, were performed on the same material. The effective stress concept, validated by a recent theoretical analysis by Coussy and Dangla (2002), was used to interpret the results. The predictions of a micromechanical model are compared with the experimental data in the elastic domain and on the failure criterion. The method highlights a simple way to relate the strength and stiffness of the soil to its negative pore water pressure.
<b>Tipo</b>: article2011-07-07T14:45:44ZA large triaxial apparatus for the study of granular materials under repeated loading used at LNEC
https://hdl.handle.net/1822/12725
Título: A large triaxial apparatus for the study of granular materials under repeated loading used at LNEC
Autor: Correia, A. Gomes; Gillett, S.
Resumo: The improvement of analytical road pavement and railway infrastructure design methods requires a rational study of the mechanical behaviour of the constituent materials. The repeated load triaxial apparatus is one of the most common and useful tools for determining the parameters used in these design methods. This paper presents a description of a repeated load triaxial apparatus designed to test unbound granular materials of up to 0/60 gradings. The importance of the compacted density in the behaviour of these materials necessitates a laboratory compaction method that reproduces the in-situ conditions. Consequently a method of compaction and control of the density is also presented. By using this apparatus the most common parameters used in analytical pavement design (resilient modulus and Poisson’s ratio) are acquired. This is illustrated by testing a 0/20 graded crushed granite used as base course for road construction. This test apparatus may also be used to investigate the permanent deformation characteristics of base course materials.
<b>Tipo</b>: conferencePaper2011-07-07T10:12:41Z