纳米SiO_2对硅酸盐水泥水化放热特性的影响

Effect of nano-SiO_2 on heat of hydration of Portland cement

以硅灰为对比,利用微量热仪研究了纳米SiO2对硅酸盐水泥24 h内水化历程、水化放热特性的影响.研究结果表明:掺入纳米SiO2的水泥试样24 h内水化历程也可划分为类似于纯硅酸盐水泥水化的5个阶段;纳米SiO2的掺入,促使诱导期、加速期和减速期的出现提前,缩短了诱导期持续的时间;提高了水化开始时的放热速率,使第二放热峰的出现提前,增大了水化放热量.

The effect of nano-silica powder compared to silicafume on the hydration Process and heat of hydration of Portland cement during 24 hours were studied. The results show that the hydration process of the sample containing nano-siliea powder during 24 hours can be divided into five periods similar to pure Portland cement and the presence of nano-silica powder increases the rate of exothermic hydration in the early period, puts ahead emergence of the dormant, acceleration and deceleration period, shortens duration of the dormant period, puts ahead emergence of second peak, increases heat evolution during 24 hours.