A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Hydration and microstructure of Portland cement partially substituted with ultrafine silica
Geothermal waste, a by-product of steam power plants that use geothermal underground resources, was studied as a possible replacement for Portland cement. This waste consists primarily in amorphous nanometric silica with traces of sodium and potassium chlorides. The replacement ratios studied were 0, 10 and 20% in cements cured at 20 and 60 ºC. X-ray diffraction analysis showed that clinker phase hydration took place earlier in the presence of the geothermal waste. Scanning electron microscopy, in turn, revealed a reduction in porosity and intense calcium hydroxide consumption as a result of the pozzolanic reaction. The pastes containing 20% waste, however, an intense cracking was observed due to the formation of alkali silica reaction gel and ettringite. Cracking was more prominent at 60 ºC but was not observed in either the neat cement or the blend with 10 % waste. The presence of these detrimental phases was attributed to the formation of Friedel’s salt in the initial hydration stages, induced by the chlorides in the geothermal material.
Hydration and microstructure of Portland cement partially substituted with ultrafine silica
Geothermal waste, a by-product of steam power plants that use geothermal underground resources, was studied as a possible replacement for Portland cement. This waste consists primarily in amorphous nanometric silica with traces of sodium and potassium chlorides. The replacement ratios studied were 0, 10 and 20% in cements cured at 20 and 60 ºC. X-ray diffraction analysis showed that clinker phase hydration took place earlier in the presence of the geothermal waste. Scanning electron microscopy, in turn, revealed a reduction in porosity and intense calcium hydroxide consumption as a result of the pozzolanic reaction. The pastes containing 20% waste, however, an intense cracking was observed due to the formation of alkali silica reaction gel and ettringite. Cracking was more prominent at 60 ºC but was not observed in either the neat cement or the blend with 10 % waste. The presence of these detrimental phases was attributed to the formation of Friedel’s salt in the initial hydration stages, induced by the chlorides in the geothermal material.
Hydration and microstructure of Portland cement partially substituted with ultrafine silica
L. Y. Gómez-Zamorano (author) / J. I. Escalante (author)
2009
Article (Journal)
Electronic Resource
Unknown
Metadata by DOAJ is licensed under CC BY-SA 1.0
Hydration of ultrafine and ordinary Portland cement at early ages
| Springer Verlag | 2014
Hydration of ultrafine and ordinary Portland cement at early ages
| Online Contents | 2014
Hydration reactions in portland cement-silica fume blends
| Elsevier | 1984
Hydration Process of Portland Cement Blended with Silica Fume
| Tema Archive | 2013