【摘要】 从性能演变的基本观点出发,研究了混凝土的水化反应过程,提出了一种混凝土热-化学耦合模型,该模型可考虑混凝土实时温度对水化放热速率的影响。混凝土温度场与化学场的耦合主要通过引入水化度来达成——将水化度作为化学反应系统物理-化学耦合场的中间变量并建立水化度与放热量之间的关系。基于热力学及化学反应动力学的基本理论,推导了水化反应化学亲和力的公式;导出了水化反应的控制方程,建立了相应的水化模型,并详述了模型在有限元方法中的实现过程;最后,结合相关试验结果对该模型进行了数值验证。更多还原

【Abstract】 From the basic standpoint of property evolution,this paper studies the hydration process of concrete and proposes a thermo-chemical coupling model for concrete.This model considers the effect of concrete real-time temperature on the rate of hydration heat release.By introducing the hydration degree,the coupling temperature field and chemical field for concrete is achieved. The hydration degree is used as the intermediate variable of chemical reaction system. Thus,physical-chemical coupling field and the relationship between hydration degree and heat release is established. Based on the basic theory of thermodynamics and chemical reaction kinetics,this paper derives a formula of chemical affinity of hydration reaction; established governing equation of hydration reaction and derived the corresponding hydration model,describes the implementation of the model in the finite element method in detail. Finally,the model is validated by the experimental results.更多还原