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Addressing sulfate-induced heave in lime treated soils / Dallas N. Little in Journal of geotechnical and geoenvironmental engineering, Vol. 136 N° 1 (Janvier 2010) 

Public ISBD [article]  in Journal of geotechnical and geoenvironmental engineering > Vol. 136 N° 1 (Janvier 2010) . - pp. 110-118 Titre : Addressing sulfate-induced heave in lime treated soils Type de document : texte imprimé Auteurs : Dallas N. Little, Auteur ; Syam Nair, Auteur ; Bruce Herbert, Auteur Article en page(s) : pp. 110-118 Note générale : Géotechnique Langues : Anglais (eng) Mots-clés : Ettringit  Nucleation  Crystal  growth  Volume  change  Soil  stabilization  Portland  cement  concrete  Volume  change  Threshold  sulfate  level  Concrete  Sulfates Index. décimale : 624.1 Infrastructures.Ouvrages en terre. Fondations. Tunnels Résumé : Civil engineers are at times required to stabilize sulfate-bearing clay soils with calcium-based stabilizers. Deleterious heaving in these stabilized soils may result over time. This paper addresses critical questions regarding the consequences of treating sulfate laden soils with calcium-based stabilizers. The authors describe the nature (chemistry and structure) of the minerals (ettringite/thaumasite) blamed for deleterious reactions and explain why these structures may lead to damage. The writers also describe the mechanisms of the mineral growth, and the extent of mineral growth based on the amount of sulfate minerals present in the soil. The writers explain why the rate of ettringite growth in treated soils should not be expected to follow a controlled rate of ettringite development such as that which normally occurs in portland cement concrete. The writers compare the rate and degree of ettringite development in soils to the classical model of nucleation and growth typical of most crystal structures. Finally, the writers evaluate the role of soil mineralogy in controlling soil behavior at varying sulfate contents and verify the existence of a threshold level of soluble sulfates in soils that can trigger substantial ettringite growth. DEWEY : 624.1 ISSN : 1090-0241 En ligne : http://ascelibrary.aip.org/vsearch/servlet/VerityServlet?KEY=JGGEFK&smode=strres [...] [article] Addressing sulfate-induced heave in lime treated soils [texte imprimé] / Dallas N. Little, Auteur ; Syam Nair, Auteur ; Bruce Herbert, Auteur . - pp. 110-118. Géotechnique Langues : Anglais (eng) in Journal of geotechnical and geoenvironmental engineering > Vol. 136 N° 1 (Janvier 2010) . - pp. 110-118 Mots-clés : Ettringit  Nucleation  Crystal  growth  Volume  change  Soil  stabilization  Portland  cement  concrete  Volume  change  Threshold  sulfate  level  Concrete  Sulfates Index. décimale : 624.1 Infrastructures.Ouvrages en terre. Fondations. Tunnels Résumé : Civil engineers are at times required to stabilize sulfate-bearing clay soils with calcium-based stabilizers. Deleterious heaving in these stabilized soils may result over time. This paper addresses critical questions regarding the consequences of treating sulfate laden soils with calcium-based stabilizers. The authors describe the nature (chemistry and structure) of the minerals (ettringite/thaumasite) blamed for deleterious reactions and explain why these structures may lead to damage. The writers also describe the mechanisms of the mineral growth, and the extent of mineral growth based on the amount of sulfate minerals present in the soil. The writers explain why the rate of ettringite growth in treated soils should not be expected to follow a controlled rate of ettringite development such as that which normally occurs in portland cement concrete. The writers compare the rate and degree of ettringite development in soils to the classical model of nucleation and growth typical of most crystal structures. Finally, the writers evaluate the role of soil mineralogy in controlling soil behavior at varying sulfate contents and verify the existence of a threshold level of soluble sulfates in soils that can trigger substantial ettringite growth. DEWEY : 624.1 ISSN : 1090-0241 En ligne : http://ascelibrary.aip.org/vsearch/servlet/VerityServlet?KEY=JGGEFK&smode=strres [...]