通过测定高钙灰水泥硬化浆体的膨胀值，探讨了膨胀值与水化时间和温度的关系；选择动力学模型进行计算，得出了反应速率常数和反应活化能等动力学参数．试验证明，细磨可以提高高钙灰中游离氧化钙的水化速率，进而改善其膨胀性能．某些外加剂可以改变高钙灰的水化反应速率．%In this paper, the hydration kinetic process of free CaO in system containing high calciumfly ash-H20 has been studied under different temperatures. The degree of hydration reaction at time twas determined by means of the volume expansion value L of hardened Portland cement-high calciumfly ash pastes. In the present experimental research it was found that the hydration is first-order reaction whose rate is directly proportional to the degree of reaction. For the hydration reaction the plot ofln L against t is a straight line and the intercept gives initial volume expansion L0 at t = 0 while therate constant k can be calculated from the slope. It was also found that the rate constant k increaseswith the increase of the temperature and the quantitative relationship between them followed Arrhenius' law and the plot of ln k against T-1 is linear for the reaction. Both frequency factor A and activation energy E a, which are known as Arrhenius parameters, were calculated. The experiment resultsalso show that the hydration reaction rate of free CaO increases while the volume expansion decreasesin the pastes through grinding high calcium fly ash. Some admixtures have influence on the kinetic parameters of the reaction.
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