A platform for research: civil engineering, architecture and urbanism
Amorphous silica in ultra-high performance concrete: First hour of hydration
Amorphous silica in the sub-micrometer size range is widely used to accelerate cement hydration. Investigations including properties of silica which differ from the specific surface area are rare. In this study, the reactivity of varying types of silica was evaluated based on their specific surface area, surface silanol group density, content of silanol groups and solubility in an alkaline suspension. Pyrogenic silica, silica fume and silica synthesized by hydrolysis and condensation of alkoxy silanes, so-called Stoeber particles, were employed. Influences of the silica within the first hour were further examined in pastes with water/cement ratios of 0.23 using in-situ X-ray diffraction, cryo scanning electron microscopy and pore solution analysis. It was shown that Stoeber particles change the composition of the pore solution. Na+, K+, Ca2+ and silicate ions seem to react to oligomers. The extent of this reaction might be highest for Stoeber particles due to their high reactivity.
Amorphous silica in ultra-high performance concrete: First hour of hydration
Amorphous silica in the sub-micrometer size range is widely used to accelerate cement hydration. Investigations including properties of silica which differ from the specific surface area are rare. In this study, the reactivity of varying types of silica was evaluated based on their specific surface area, surface silanol group density, content of silanol groups and solubility in an alkaline suspension. Pyrogenic silica, silica fume and silica synthesized by hydrolysis and condensation of alkoxy silanes, so-called Stoeber particles, were employed. Influences of the silica within the first hour were further examined in pastes with water/cement ratios of 0.23 using in-situ X-ray diffraction, cryo scanning electron microscopy and pore solution analysis. It was shown that Stoeber particles change the composition of the pore solution. Na+, K+, Ca2+ and silicate ions seem to react to oligomers. The extent of this reaction might be highest for Stoeber particles due to their high reactivity.
Amorphous silica in ultra-high performance concrete: First hour of hydration
Oertel, Tina (author) / Hutter, Frank (author) / Helbig, Uta (author) / Sextl, Gerhard (author)
Cement and Concrete Research ; 58 ; 131-142
2014
12 Seiten, 70 Quellen
Article (Journal)
English
Amorphous silica in ultra-high performance concrete: First hour of hydration
British Library Online Contents | 2014
|Amorphous silica in ultra-high performance concrete: First hour of hydration
Online Contents | 2014
|Influence of amorphous silica on the hydration in ultra-high performance concrete
British Library Online Contents | 2014
|Influence of amorphous silica on the hydration in ultra-high performance concrete
Online Contents | 2014
|Influence of amorphous silica on the hydration in ultra-high performance concrete
Tema Archive | 2014
|