Silica fume hydration

Silicon Dioxide occurs as an amorphous substance that shows a noncrystalline pattern when examined by X-ray diffraction. It is produced synthetically, either by a vapor-phase hydrolysis process, yielding fumed silica, or by a wet process, yielding precipitated silica, silica gel, colloidal silica, or hydrous silica. Fumed silica is produced in an essentially anhydrous state, whereas the wet-process products are obtained as hydrates or contain surface-adsorbed water. 

Cement hydration and pozzolanic reaction of silica fume that increased the concrete strength ... 

When a high early strength is required, such as for post-tensioned structures or pre-tensioned precast elements, Portland cement with a strength class of 52.5 may be used. Blended cements are usually not suitable because of the slow rate of hydration, with the exception of Portland-silica fume cement and special (fast) slag cements. 

Fig. 6.15 Effect of silica fume addition on the construction of paste-aggregate transition zone eg—cement grains,. sf silica fume, (a, b) c, d hydration progress. (According to [23])...

See also Diatomaceous earth Quartz Silica, amorphous Silica, amorphous hydrated Silica, colloidal Silica, fumed Silica gel Silica, hydrated... 

Silica, precipitated. See Silica, hydrated Silica, pyrogenic. See Silica, fumed Silica, quartz. See Quartz Silica sol. See Silica, colloidal... 

Aluminum hydroxide Aluminum silicate, Boron carbide Carbon black Carbon fiber, Cellulose, Feldspar Graphite LX-782 Poly/inyl chloride Slllce Silica, amorphous hydrated. Silica, fumed,... 

See aiso Silica, amorphous hydrated Silica, fumed... 

Propiolactone Propyl alcohol Propylene carbonate Propylene glycol cocoate Propylene glycol laurate adhesive, food packaging Propylene glycol stearate Rapeseed (Brassica campestris) oil Rice (Oryza sativa) bran oil Rice (Oryza sativa) starch Rosin Rosin, polymerized Safflower (Carthamus tinctorius) oil Sandarac (Callitris quadrivalvis) gum Sebacic acid Sesame (Sesamum indicum) oil Shark liver oil Shellac Silica Silica, amorphous Silica, fumed Silica, hydrated Silicone emulsion Sodium alum Sodium bisulfate Sodium borate Sodium borate decahydrate Sodium chlorate Sodium chlorite Sodium chromate Sodium cocoate... 

Nonoxynol-3 Nonoxynol-55 Nonoxynol-70 Nonyl nonoxynol-7 Nonyl nonoxynol-8 Nonyl nonoxynol-10 Nonyl nonoxynol-150 Oleth-8 Oleth-12 Oleth-15 Oleth-20 Oleth-23 Oleth-25 Oleth-40 Oleth-50 PEG-4 dilaurate PEG-8 dioleate PEG-8 oleate PEG-12 oleate PEG-12 ricinoleate PEG-2 stearate PEG-8 stearate PEG-10 tetramethyl decynediol PEG-30 tetramethyl decynediol Potassium oleic sulfate Rosin, polymerized Silica, amorphous Silica, fumed Silica, hydrated Silicone emulsion Sulfated castor oil Tall oil glycerides Trideceth-18... 

Xi, Y., Siemer, D.D., and Scheetz, B.E. (1997) Strength developmenf hydration reaction and pore stracture of autoclaved slag cement with added silica fume. Cement and Concrete Research 27,75-82. 

Coleman, N.J., and Page, C.L. (1997) Aspects of pore solution chemistry of hydrated cement pastes containing metakaolin. Cement and Concrete Research 27,147-154. Cong, X. et al. (1992) Role of silica fume in compressive strength of cement paste, mortar and concrete. ACl Materials Journal 89,375-379. 

Durekovic, A. (1986) Hydration of ahte and CjA and chances of some stractural characteristics of cement pastes by addition of silica fume, in Proceedings 8th ICCC, Rio de Janeiro, Vol. 4, pp. 279-284. 

Durekovic, A., and Popovic, K. (1987) The influence of silica fume on the mono/disilicate anion ratio dirring the hydration of CSF containing cement paste. Cement and Concrete Research 17,108-114. 

Lilkov, V., Dimitrova, E., and Petrov, O.E. (1997) Hydration process of cement containing fly ash and silica fume the first 24 hours. Cement and Concrete Research 27, 577-588. 

Mak, S.L., and Torii, K. (1995) Strength development of high strength concretes with and without silica fume under the inflnence of high hydration temperature. Cement and Concrete Research 25, 1791-1802. 

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