水胶比和组成对补偿收缩胶凝材料的水化反应的影响

INFLUENCE OF WATER - BINDER RATIO AND COMPOSITION ON THE HYDRATION OF SHRINKAGE - COMPENSATING BINDING MATERIAL

在不同水胶比条件下,利用等温量热法测量了不同组成的补偿收缩胶凝材料的水化放热速率和放热量曲线,以评价其水化特性及其对强度和膨胀性能的影响。随着水胶比逐渐降低,水化受到抑制。在水胶比为0.3时,补偿收缩胶凝材料的总放热量和水化放热速率有明显降低。由矿物掺和料、膨胀剂和硅酸盐水泥组成的复合胶凝材料的总放热量和水化放热速率较低,但后期水化放热增加量较大。水胶比大于0.4后,水胶比的变化对复合胶凝材料的水化过程影响很小。

The calorimetric data of shrinkage-compensating binding materials with different compositions were measured at different water-binder ratios using a differential calorimeter. The hydration characteristics of the shrinkage-compensating binders were evaluated and their influence on the strength and expansive properties of the shrinkage-compensating binders was discussed. It is found that the hydration is suppressed when the water-binder ratio decreases gradually. The total hydration heat and the rate of heat evolution reduce obviously at the time of m(w)/m(b)=0.3. The high expansive efficiency of the binder is obtained only with appropriate m(w)/m(b). The hydration heat and the rate of heat evolution of the complex binder consisting of portland cement, mineral admixture and expansive agent are lower than those of plain portland cement, but there is a high increase of these values in the later period of hydration. The influence of the variance of m(w)/m(b) on the hydration process of the complex binder decreases when the water-binder ratio is larger than 0.4.