纳米氧化铝对硅酸盐水泥浆体流变、水化和硬化强度的影响

Effect of Nano-Alumina on Rheological Property,Hydration and Hardening Strength of Portland Cement Paste

本文研究了纳米氧化铝(NA)对硅酸盐水泥浆体的早期流变性、中期水化特性和后期力学性能的影响,并且分析了三个阶段之间参数的相关性。结果表明,NA的掺入增大了新拌水泥浆体的屈服应力和塑性黏度,且当NA掺量范围为3%~5%时,屈服应力和塑性黏度最大增幅均超过110%。在水泥浆体中掺入NA明显改变了硅酸盐水泥早期的水化放热速率和放热量,并且使得浆体在各龄期的抗压强度和抗折强度有所增长。对于该复合胶凝体系,早期的水化放热量与流变参数呈指数增长的变化趋势,而放热峰值速率与抗压强度则存在近似线性的函数关系。

The effects of nano-alumina(NA)on the early rheological properties,mid-term hydration rate and long-term mechanical properties of Portland cement pastes were studied,and the correlation of these parameters were analyzed.Results show that the addition of NA increases the yield stress and plastic viscosity of fresh cement paste,and the maximum growth rates of these two parameters are more than 110%when NA content is 3%to 5%.NA significantly changes the hydration heat flow rate and heat release of Portland cement in the early stage,and increases the compressive strength and bending strength of paste at various ages.For this composite paste system,the early hydration heat release and rheological parameters show an exponential growth trend,while the peak rate of heat flow has an approximate linear function relationship with the compressive strength.