基于微观信息的水泥水化动力学模型研究

Research on Kinetics Model of Cement Hydration Based on Microstructure Information

关键词:  水化模型  水泥净浆  水化过程  水化度  孔隙率

Key words:  hydration model  cement paste  hydration process  hydration degree  porosity

摘要:

为了精确预测水泥水化过程，分析水泥水化过程中微观结构的时变发展规律，提出了水化单元的概念；基于水泥水化的微观信息，采用Krstulovic＇ Dabic＇水化反应动力学方程式，构建了水泥水化度与微观结构之间的联系，考虑了水灰比、水泥化学组分、孔隙水分、温度、水泥颗粒与水的接触面积、水泥颗粒粒径分布等因素对水泥水化过程的影响，建立了改进的水泥水化动力学模型.通过热重分析、压汞试验等一系列试验方法，分析了水泥净浆的水化度、孔隙率等特征参数随时间的发展变化规律.试验结果与模型预测结果吻合良好，表明所建立的模型可以较准确地模拟水泥水化过程的时变发展规律.

Abstract:

In order to accurately predict the cement hydration process and analyze the time dependence of microstructure development of cement during hydration process, the concept of hydration unit was proposed to establish the relationship between cement hydration degree and microstructure based on microstructure information and Krstulovic＇ Dabic＇ hydration kinetics formulas.Taking water cement ratio, chemical compositions of cement, free water in porosity, temperature, interfacial contact area between hydration products and free water and diameter distribution of cement particles into consideration, an improved kinetics model of cement hydration was established.The thermo gravimetric analysis and differential thermal analysis (TGA) and mercury intrusion test were employed to study the development of hydration degree and porosity of cement paste.The experiment results agree well with the model prediction results, which indicate that the model can accurately simulate the time dependent development of cement hydration process.