2011 Volume 65 Issue 1 Pages 456-463
The water-binder ratio of ultra high strength concrete is extremely low；therefore the addition of low-heat portoland cement（LC）, moderate-heat portland cement（MC）and silica fume is indispensable at mixing. This research was conducted to elucidate how was different in water-binder ratio, would affect the compressive strength and hydrate of low-heat portland cement if added to the cement along with silica fume. The influences were discussed from the perspectives of cement hydration required by the Rietveld method using powder X-ray diffraction（XRD）, silica fume hydration by the selective dissolution method and silicate-chain polymerization of hydrate calcium silicate（C-S-H）by the trimethylsilyl（TMS）derivatization method. As for the water-binder ratio of 15％ mixing used with the ultra high strength concrete, a reactive rate of SF was low and the amount of the C-S-H generation was a little though compressive strength had risen compared with water-binder ratios of 30％ and 22％ mixing. The extent of polymerization of the silicate anion has decreased to the influence of W/B on the silicate anion polymerization level as W/B lowers. The addition of silica fume promoted polymerization.
