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An investigation of microstructure evolution in cement paste through setting using ultrasonic and rheological measurements / Kolluru V. Subramaniam in Cement and concrete research, Vol. 40 N° 1 (Janvier 2010) 

Public ISBD [article]  in Cement and concrete research > Vol. 40 N° 1 (Janvier 2010) . - pp. 33-44 Titre : An investigation of microstructure evolution in cement paste through setting using ultrasonic and rheological measurements Type de document : texte imprimé Auteurs : Kolluru V. Subramaniam, Auteur ; Xiaojun Wang, Auteur Article en page(s) : pp. 33-44 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Microstructure  Porosity  Rheology  Ultrasonic  Testing  Setting Index. décimale : 691 Matériaux de construction. Pièces et parties composantes Résumé : The response of hydrating cement paste through setting are monitored using rheological measurements and ultrasonic reflection measurements. Increases in the elastic modulus and yield stress of cement paste with time are obtained from the rheological measurements. Ultrasonic measurements are performed using horizontally polarized shear waves (SH) reflected off of the hydrating cement paste. Changes in the ultrasonic signal through setting are related with changes in the porosity and stiffness of an equivalent water-filled poroelastic material, which provides identical acoustic impedance. The measured changes in the shear modulus obtained from ultrasonic measurement are shown to correlate well with increase in elastic modulus obtained from rheological measurements. The increase in the shear modulus of the porous material obtained from the ultrasonic measurements is shown to correspond well with the observed increase in the yield stress of the cement paste. By combining the information from rheological and ultrasonic measurements, it is found that even in the fluid stage there is sufficient structural integrity in the arrangement of cement grains to support low-amplitude shear stress and the evolution of a continuously connected network of cement particles within the paste is coincident with a rapid increase in the shear modulus of the porous skeleton. DEWEY : 620.13 ISSN : 0008-8846 En ligne : http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TWG-4XHJX8K-1&_user=6 [...] [article] An investigation of microstructure evolution in cement paste through setting using ultrasonic and rheological measurements [texte imprimé] / Kolluru V. Subramaniam, Auteur ; Xiaojun Wang, Auteur . - pp. 33-44. Génie Civil Langues : Anglais (eng) in Cement and concrete research > Vol. 40 N° 1 (Janvier 2010) . - pp. 33-44 Mots-clés : Microstructure  Porosity  Rheology  Ultrasonic  Testing  Setting Index. décimale : 691 Matériaux de construction. Pièces et parties composantes Résumé : The response of hydrating cement paste through setting are monitored using rheological measurements and ultrasonic reflection measurements. Increases in the elastic modulus and yield stress of cement paste with time are obtained from the rheological measurements. Ultrasonic measurements are performed using horizontally polarized shear waves (SH) reflected off of the hydrating cement paste. Changes in the ultrasonic signal through setting are related with changes in the porosity and stiffness of an equivalent water-filled poroelastic material, which provides identical acoustic impedance. The measured changes in the shear modulus obtained from ultrasonic measurement are shown to correlate well with increase in elastic modulus obtained from rheological measurements. The increase in the shear modulus of the porous material obtained from the ultrasonic measurements is shown to correspond well with the observed increase in the yield stress of the cement paste. By combining the information from rheological and ultrasonic measurements, it is found that even in the fluid stage there is sufficient structural integrity in the arrangement of cement grains to support low-amplitude shear stress and the evolution of a continuously connected network of cement particles within the paste is coincident with a rapid increase in the shear modulus of the porous skeleton. DEWEY : 620.13 ISSN : 0008-8846 En ligne : http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TWG-4XHJX8K-1&_user=6 [...]