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Colloidal silica transport through liquefiable porous media / Patricia M. Gallagher in Journal of geotechnical and geoenvironmental engineering, Vol. 135 N° 11 (Novembre 2009) 

Public ISBD [article]  in Journal of geotechnical and geoenvironmental engineering > Vol. 135 N° 11 (Novembre 2009) . - pp. 1702–1712 Titre : Colloidal silica transport through liquefiable porous media Type de document : texte imprimé Auteurs : Patricia M. Gallagher, Auteur ; Yuanzhi Lin, Auteur Année de publication : 2009 Article en page(s) : pp. 1702–1712 Note générale : Geotechnical and geoenvironmental engineering Langues : Anglais (eng) Mots-clés : ColloidsSilicaSoil  liquefactionGroutingSoil  stabilizationPorous  media Résumé : Mitigation of liquefaction potential in loose granular soil can theoretically be achieved through permeation and subsequent gelation of dilute colloidal silica stabilizer. However, practical application of this technique requires efficient and adequate delivery of the stabilizer to the liquefiable soil prior to gelation. The purpose of this research was to evaluate colloidal silica transport mechanisms and to determine if an adequate concentration can be delivered to a soil column prior to gelation. The laboratory work consisted of grouting 15 short (0.9 m) columns tests packed with Nevada No. 120, Ottawa 20/30, or graded silty sand to identify the variables that influence stabilizer transport through porous media. It was found that colloidal silica can be successfully delivered through 0.9-m columns packed with loose sand efficiently and in an adequate concentration to mitigate the liquefaction potential. Transport occurs primarily by advection with limited hydrodynamic dispersion, so Darcy’s law can be used to predict flow. The Kozeny-Carmen equation can be used to include the effect of increasing viscosity on transport by incorporating the power law mixing rule of Todd. The primary variables influencing stabilizer transport were found to be the viscosity of the colloidal silica stabilizer, the hydraulic gradient, and the hydraulic conductivity of the liquefiable soil. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29GT.1943-5606.0000123 [article] Colloidal silica transport through liquefiable porous media [texte imprimé] / Patricia M. Gallagher, Auteur ; Yuanzhi Lin, Auteur . - 2009 . - pp. 1702–1712. Geotechnical and geoenvironmental engineering Langues : Anglais (eng) in Journal of geotechnical and geoenvironmental engineering > Vol. 135 N° 11 (Novembre 2009) . - pp. 1702–1712 Mots-clés : ColloidsSilicaSoil  liquefactionGroutingSoil  stabilizationPorous  media Résumé : Mitigation of liquefaction potential in loose granular soil can theoretically be achieved through permeation and subsequent gelation of dilute colloidal silica stabilizer. However, practical application of this technique requires efficient and adequate delivery of the stabilizer to the liquefiable soil prior to gelation. The purpose of this research was to evaluate colloidal silica transport mechanisms and to determine if an adequate concentration can be delivered to a soil column prior to gelation. The laboratory work consisted of grouting 15 short (0.9 m) columns tests packed with Nevada No. 120, Ottawa 20/30, or graded silty sand to identify the variables that influence stabilizer transport through porous media. It was found that colloidal silica can be successfully delivered through 0.9-m columns packed with loose sand efficiently and in an adequate concentration to mitigate the liquefaction potential. Transport occurs primarily by advection with limited hydrodynamic dispersion, so Darcy’s law can be used to predict flow. The Kozeny-Carmen equation can be used to include the effect of increasing viscosity on transport by incorporating the power law mixing rule of Todd. The primary variables influencing stabilizer transport were found to be the viscosity of the colloidal silica stabilizer, the hydraulic gradient, and the hydraulic conductivity of the liquefiable soil. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29GT.1943-5606.0000123