道路水泥性能及其水化动力学研究

RESEARCH ON PROPERTIES AND HYARATION KINETICS OF ROAD CEMENT

应用恒温导热法等研究了道路水泥的水化动力学过程以及ＣａＯ、石膏对其水化过程和性能的影响。研究结果表明，与硅酸盐水泥、普通硅酸盐水泥相比，道路水泥由于其特有的矿物组成，尽管早期水化放热速率和水化放热量较低，但早期强度较高，而且具有初凝时间较长，初、终凝时间间隔较短、耐磨、抗干缩等性能，能较好地适应道路建筑工程需要。道路水泥在不同水化阶段具有不同的反应机理，所适用的动力学公式及动力学参数也不同，外掺ＣａＯ可使其水化减速期动力学过程得以改变，但掺入少量ＣａＯ对道路水泥的性能影响不大。

he kinetics of hydration for road cement and the influence of doped CaO and gypsum on its hydration and performance were studied by isothermal conductive calorimetry and other methods. The result revealed that although the rate of heat flow and the total heat output of the road cement during its hydration process were lower than those of Portland cement and ordinary Portland cement because of its special mineral composition, it had a rapid development in strength .a longer initial setting time and shorter interval between illitial and final setting as well as a good behaviour to resist sulfate,abrasion and dry shrinkage. The kinetics and mechanism of its hydration were changed at different stages, and the kinetic parameters were also different. The hydration was controlled by autocatalytic reaction at the acceleration stage and by diffusion at the decay stage. The hydration process at deceleration stage was changed from being controlled by autocatalytic reaction to being controlled by boundary reaction according to doping with CaO, but the doped CaO had no evident effect on the performance of the cement after the cement passing the Le Chatelier soundness test.