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Effect of the porosity/cement ratio on the compression of cemented soil / Sara Rios in Journal of geotechnical and geoenvironmental engineering, Vol. 138 N° 11 (Novembre 2012) 

Public ISBD [article]  in Journal of geotechnical and geoenvironmental engineering > Vol. 138 N° 11 (Novembre 2012) . - pp. 1422-1426 Titre : Effect of the porosity/cement ratio on the compression of cemented soil Type de document : texte imprimé Auteurs : Sara Rios, Auteur ; António Viana Da Fonseca, Auteur ; Béatrice Anne Baudet, Auteur Année de publication : 2013 Article en page(s) : pp. 1422-1426 Note générale : Géotechnique Langues : Anglais (eng) Mots-clés : Soil-cement  Porosity/cement  ratio  Normal  compression  line  Isotropic  compression Résumé : The compression behavior of an artificially cemented soil was analyzed by the adjusted porosity/cement index using a correlation established in the recent literature. It was found that for each value of this index, defined as the ratio of porosity to the volumetric cement content, there was a unique normal compression line (NCL). The NCLs of the cemented specimens for each adjusted porosity/cement index did not converge with the NCL of the uncemented silty sand at large stresses, but reached a line parallel to it. The NCL of the cemented sand plotted further from the NCL of the uncemented sand as the porosity/cement index decreased. ISSN : 1090-0241 En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29GT.1943-5606.0000698 [article] Effect of the porosity/cement ratio on the compression of cemented soil [texte imprimé] / Sara Rios, Auteur ; António Viana Da Fonseca, Auteur ; Béatrice Anne Baudet, Auteur . - 2013 . - pp. 1422-1426. Géotechnique Langues : Anglais (eng) in Journal of geotechnical and geoenvironmental engineering > Vol. 138 N° 11 (Novembre 2012) . - pp. 1422-1426 Mots-clés : Soil-cement  Porosity/cement  ratio  Normal  compression  line  Isotropic  compression Résumé : The compression behavior of an artificially cemented soil was analyzed by the adjusted porosity/cement index using a correlation established in the recent literature. It was found that for each value of this index, defined as the ratio of porosity to the volumetric cement content, there was a unique normal compression line (NCL). The NCLs of the cemented specimens for each adjusted porosity/cement index did not converge with the NCL of the uncemented silty sand at large stresses, but reached a line parallel to it. The NCL of the cemented sand plotted further from the NCL of the uncemented sand as the porosity/cement index decreased. ISSN : 1090-0241 En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29GT.1943-5606.0000698

Fundamental parameters for the stiffness and strength control of artificially cemented sand / Nilo Cesar Consoli in Journal of geotechnical and geoenvironmental engineering, Vol. 135 N° 9 (Septembre 2009) 

Public ISBD [article]  in Journal of geotechnical and geoenvironmental engineering > Vol. 135 N° 9 (Septembre 2009) . - pp. 1347–1353 Titre : Fundamental parameters for the stiffness and strength control of artificially cemented sand Type de document : texte imprimé Auteurs : Nilo Cesar Consoli, Auteur ; António Viana Da Fonseca, Auteur ; Rodrigo Caberlon Cruz, Auteur Année de publication : 2009 Article en page(s) : pp. 1347–1353 Note générale : Geotechnical and geoenvironmental engineering Langues : Anglais (eng) Mots-clés : CementsCompression  testsTriaxial  testsSoil  compactionSubgradesRailroad  tracks Résumé : The treatment of soils with cement is an attractive technique when the project requires improvement of the local soil for the construction of subgrades for rail tracks, as a support layer for shallow foundations and to prevent sand liquefaction. As reported by Consoli et al. in 2007, a unique dosage methodology has been established based on rational criteria where the voids/cement ratio plays a fundamental role in the assessment of the target unconfined compressive strength. The present study broadened the research carried out by Consoli et al. in 2007 through quantifying quantifies the influence of voids/cement ratio on the initial shear modulus (G0) and Mohr-Coulomb effective strength parameters (c′,ϕ′) of an artificially cemented sand. A number of unconfined compression and triaxial compression tests with bender elements measurements were carried out. It was shown that the void/cement ratio defined as the ratio between the volume of voids of the compacted mixture and the volume of cement is an appropriate parameter to assess both initial stiffness and effective strength of the sand-cement mixture studied. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29GT.1943-5606.0000008 [article] Fundamental parameters for the stiffness and strength control of artificially cemented sand [texte imprimé] / Nilo Cesar Consoli, Auteur ; António Viana Da Fonseca, Auteur ; Rodrigo Caberlon Cruz, Auteur . - 2009 . - pp. 1347–1353. Geotechnical and geoenvironmental engineering Langues : Anglais (eng) in Journal of geotechnical and geoenvironmental engineering > Vol. 135 N° 9 (Septembre 2009) . - pp. 1347–1353 Mots-clés : CementsCompression  testsTriaxial  testsSoil  compactionSubgradesRailroad  tracks Résumé : The treatment of soils with cement is an attractive technique when the project requires improvement of the local soil for the construction of subgrades for rail tracks, as a support layer for shallow foundations and to prevent sand liquefaction. As reported by Consoli et al. in 2007, a unique dosage methodology has been established based on rational criteria where the voids/cement ratio plays a fundamental role in the assessment of the target unconfined compressive strength. The present study broadened the research carried out by Consoli et al. in 2007 through quantifying quantifies the influence of voids/cement ratio on the initial shear modulus (G0) and Mohr-Coulomb effective strength parameters (c′,ϕ′) of an artificially cemented sand. A number of unconfined compression and triaxial compression tests with bender elements measurements were carried out. It was shown that the void/cement ratio defined as the ratio between the volume of voids of the compacted mixture and the volume of cement is an appropriate parameter to assess both initial stiffness and effective strength of the sand-cement mixture studied. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29GT.1943-5606.0000008

Influence of cement-voids ratio on stress-dilatancy behavior of artificially cemented sand / Nilo Cesar Consoli in Journal of geotechnical and geoenvironmental engineering, Vol. 138 N° 1 (Janvier 2012) 

Public ISBD [article]  in Journal of geotechnical and geoenvironmental engineering > Vol. 138 N° 1 (Janvier 2012) . - pp. 100-109 Titre : Influence of cement-voids ratio on stress-dilatancy behavior of artificially cemented sand Type de document : texte imprimé Auteurs : Nilo Cesar Consoli, Auteur ; Rodrigo Caberlon Cruz, Auteur ; António Viana Da Fonseca, Auteur Année de publication : 2012 Article en page(s) : pp. 100-109 Note générale : Géotechnique Langues : Anglais (eng) Mots-clés : Stress-dilatancy  Cement-voids  ratio  Triaxial  tests  Soil-cement Résumé : The addition of cement is an interesting remediation technique when the project requires improvement of the local soil for the construction of pavement base layers, in slope protection of earth dams and canal linings, as a support layer for shallow foundations and to prevent sand liquefaction. The present study was carried out to quantify the influence of the amount of cement and the porosity in a cement-voids ratio, defined as the ratio between the volume of cement and the volume of voids of a mixture, on the stress-dilatancy behavior of an artificially cemented sand. A program of triaxial compression tests considering three distinct cement-voids ratios was carried out with two combinations of volumes of voids and volumes of cement at each cement-voids ratio. Results showed that the stress-dilatancy relationship is alike for a given cement-voids ratio and that the stress-strain behavior is also similar. The cement-voids ratio is therefore an appropriate parameter to assess stress-dilatancy of the sand-cement mixture studied. DEWEY : 624.1 ISSN : 1090-0241 En ligne : http://ascelibrary.org/gto/resource/1/jggefk/v138/i1/p100_s1?isAuthorized=no [article] Influence of cement-voids ratio on stress-dilatancy behavior of artificially cemented sand [texte imprimé] / Nilo Cesar Consoli, Auteur ; Rodrigo Caberlon Cruz, Auteur ; António Viana Da Fonseca, Auteur . - 2012 . - pp. 100-109. Géotechnique Langues : Anglais (eng) in Journal of geotechnical and geoenvironmental engineering > Vol. 138 N° 1 (Janvier 2012) . - pp. 100-109 Mots-clés : Stress-dilatancy  Cement-voids  ratio  Triaxial  tests  Soil-cement Résumé : The addition of cement is an interesting remediation technique when the project requires improvement of the local soil for the construction of pavement base layers, in slope protection of earth dams and canal linings, as a support layer for shallow foundations and to prevent sand liquefaction. The present study was carried out to quantify the influence of the amount of cement and the porosity in a cement-voids ratio, defined as the ratio between the volume of cement and the volume of voids of a mixture, on the stress-dilatancy behavior of an artificially cemented sand. A program of triaxial compression tests considering three distinct cement-voids ratios was carried out with two combinations of volumes of voids and volumes of cement at each cement-voids ratio. Results showed that the stress-dilatancy relationship is alike for a given cement-voids ratio and that the stress-strain behavior is also similar. The cement-voids ratio is therefore an appropriate parameter to assess stress-dilatancy of the sand-cement mixture studied. DEWEY : 624.1 ISSN : 1090-0241 En ligne : http://ascelibrary.org/gto/resource/1/jggefk/v138/i1/p100_s1?isAuthorized=no

Voids/cement ratio controlling tensile strength of cement-treated soils / Nilo Cesar Consoli in Journal of geotechnical and geoenvironmental engineering, Vol. 137 N° 11 (Novembre 2011) 

Public ISBD [article]  in Journal of geotechnical and geoenvironmental engineering > Vol. 137 N° 11 (Novembre 2011) . - pp. 1126-1131 Titre : Voids/cement ratio controlling tensile strength of cement-treated soils Type de document : texte imprimé Auteurs : Nilo Cesar Consoli, Auteur ; António Viana Da Fonseca, Auteur Année de publication : 2012 Article en page(s) : pp. 1126-1131 Note générale : Géotechnique Langues : Anglais (eng) Mots-clés : Cemented  soil  Porosity  Tensile  strength  Compacted  soils  Voids/cement  ratio Résumé : The improvement of locally available soils with cement can provide great advantages, including avoiding the need to borrow volumes of appropriate material and disposing of the local soil in deposits. This research aims to quantify the influence of the amount of cement, the porosity, and the voids/cement ratio in the assessment of splitting tensile strength (qt), also known as indirect diametrical tensile (IDT) strength, of three distinct soils from Brazil and Portugal. From Brazil, clayey sand derived from Botucatu sandstone and uniform Osorio sand were considered; from Portugal, silty sand derived from weathered Porto granite was studied. A number of splitting tensile strength tests were carried out. The results show that qt increased with the amount of cement (C) and decreases in porosity (η) for the three soil-cement mixtures. A power function was well-adapted to fit both qt-C and qt-η. Finally, the tensile strength was plotted against the porosity/volumetric cement content relationship (η/Civ), in which volumetric cement content is adjusted by a different exponent depending on the soil (0.21 for Porto silty sand-cement mixtures, 0.28 for Botucatu clayey sand-cement mixtures, and 1.0 for Osorio sand-cement mixtures). These plots show unique correlations for each soil-cement mixture, indicating that the index property is a good parameter in the evaluation of the splitting tensile strength of the soils studied. As a consequence, for each of the three soil-cement mixtures studied, a target qt value could be obtained by both porosity reduction and cement increase. This experimental framework will enable a good definition of the mechanical parameters used in the design of foundations and subgrades of railways platforms, whose system failure mechanisms usually start under tensile stresses at the base of the improved layer, and in the execution quality control of such earthworks. DEWEY : 624.1 ISSN : 1090-0241 En ligne : http://ascelibrary.org/gto/resource/1/jggefk/v137/i11/p1126_s1?isAuthorized=no [article] Voids/cement ratio controlling tensile strength of cement-treated soils [texte imprimé] / Nilo Cesar Consoli, Auteur ; António Viana Da Fonseca, Auteur . - 2012 . - pp. 1126-1131. Géotechnique Langues : Anglais (eng) in Journal of geotechnical and geoenvironmental engineering > Vol. 137 N° 11 (Novembre 2011) . - pp. 1126-1131 Mots-clés : Cemented  soil  Porosity  Tensile  strength  Compacted  soils  Voids/cement  ratio Résumé : The improvement of locally available soils with cement can provide great advantages, including avoiding the need to borrow volumes of appropriate material and disposing of the local soil in deposits. This research aims to quantify the influence of the amount of cement, the porosity, and the voids/cement ratio in the assessment of splitting tensile strength (qt), also known as indirect diametrical tensile (IDT) strength, of three distinct soils from Brazil and Portugal. From Brazil, clayey sand derived from Botucatu sandstone and uniform Osorio sand were considered; from Portugal, silty sand derived from weathered Porto granite was studied. A number of splitting tensile strength tests were carried out. The results show that qt increased with the amount of cement (C) and decreases in porosity (η) for the three soil-cement mixtures. A power function was well-adapted to fit both qt-C and qt-η. Finally, the tensile strength was plotted against the porosity/volumetric cement content relationship (η/Civ), in which volumetric cement content is adjusted by a different exponent depending on the soil (0.21 for Porto silty sand-cement mixtures, 0.28 for Botucatu clayey sand-cement mixtures, and 1.0 for Osorio sand-cement mixtures). These plots show unique correlations for each soil-cement mixture, indicating that the index property is a good parameter in the evaluation of the splitting tensile strength of the soils studied. As a consequence, for each of the three soil-cement mixtures studied, a target qt value could be obtained by both porosity reduction and cement increase. This experimental framework will enable a good definition of the mechanical parameters used in the design of foundations and subgrades of railways platforms, whose system failure mechanisms usually start under tensile stresses at the base of the improved layer, and in the execution quality control of such earthworks. DEWEY : 624.1 ISSN : 1090-0241 En ligne : http://ascelibrary.org/gto/resource/1/jggefk/v137/i11/p1126_s1?isAuthorized=no