【作者】 赵鹏；

【导师】 徐德龙； 李晓光；

【作者基本信息】 西安建筑科技大学 ， 材料学， 2006， 硕士

【摘要】 矿渣微粉作为水泥混凝土的掺和料已得到广泛应用。它的制备工艺经历了矿渣与水泥混合粉磨到矿渣单独粉磨的转变。单独粉磨矿渣不仅能有效的提高矿渣的细度,而且使其大规模生产和循环利用成为可能。但是这种新的制备方法在应用中仍然存在一些新的问题,如新拌水泥浆体的需水量提高、水泥石早期强度下降等。为此本文重点是研究矿渣—水泥体系颗粒群特征及其早期性能之间的关系。 本研究采用四种不同的表征方法:比表面积、粉体堆积密度、均匀性系数和粉体的分形维数,共同描述矿渣水泥颗粒群的细度和粒度分布的特征。采用新拌浆体的密度、标准稠度用水量和流动度共同反映新拌矿渣水泥的需水量问题。在全部的研究工作中,所使用的新拌浆体水灰比均保持不变。主要的研究结果如下: 在水灰比不变的条件下,矿渣粉与水泥粉体颗粒混合后的堆积密度越大,矿渣水泥中的填充水越少,包裹水量增加。同时可以提高矿渣水泥的流动性,缓解由于矿渣粉比表面积的增加所引起的需水量增大的问题。由于在掺入矿粉的硬化水泥石中,矿渣粉不但具有物理填充作用,同时具备化学作用,所以干拌的混合粉体的堆积密度与硬化水泥石强度之间没有显著的对应关系。 在矿渣水泥配比不变的条件下,当所掺入的矿渣粉比表面积相同时,随着其均匀性系数的减小(矿渣的粒度分布变宽),矿渣水泥需水量变小,新拌合浆体的相对密度变大。减少矿渣粉的均匀性系数,能够使早期的硬化水泥石中孔结构得到优化,提高了水泥石的早期强度。通过对均匀性系数以及混合粉体的堆积密度分析可知:矿渣粉的均匀性系数对矿渣水泥的3天强度影响显著;提高混合粉体的堆积密度,有利于增加水泥石28天的强度。 当矿渣粉的比表面积不同时,随着矿渣和熟料混合粉体中颗粒群分形维数的增更多还原

【Abstract】 The slag powder had been widely used as the additive in the cement and concrete. The preparation technology had changed from mixed grind to separate grind of the slag and cement. The separate grind of slag not only could improved the slag finesse but also made it possible to product it cosmically and recycling. But new problems appear in the application of the new method, such as the improvement of water requirement in fresh paste, and drop the early strength of cement stone. So emphases of the paper were discussed the relationship between the particle group characters of slag cement and the performance in the early day.The study adopts four token methods: specific surface, packing density, uniformity coefficient and fractal dimension, and used these methods to describe the finesse and particle distribution of the slag cement particle group. Adopt relative density of fresh paste, water consumption of standard consistence and fluidity to reflect the water requirement of fresh paste together. Fresh paste keeps the same water cement ratios in study work. The mainly results of the investigation were list as follow:Fixed the water cement ratio, the packing water reduced with the increasing of the slag and cement particle’s packing density, but rewrap water is increased at the same time. It can improve fluidity of slag cement, and slow the increasing of the water requirement which caused by improvement of the slag’s specific surface. Slag was play not only an role of physical filling effect but also an role of chemical effect in slag cement. So there is no notable relationship between the powder’s packing density and the strength of slag cement stone.Keep the same ratio of slag and cement. When the specific surface of slag is the same, the water requirement of slag cement reduced and the relative density of freshpaste increased with the increasing of uniformity coefficient. It can optimist the pore structure and improve the early strength of the slag cement stone. Two conclusions can be drawn from the analysis of uniformity coefficient and powder’s packing density: the slag’s uniformity coefficient mainly affect on compressive strength of slag cement in 3 day;the improvement of the powder’s packing density is propitious to increase the strength of cement stone in 28 day.When the specific surface is difference, the fresh paste relatively density improved with the increasing of slag cement powder’s fractal dimension. When the percent of slag is more than 50%, the increasing trend of slag cement’s strength is becoming more and more obviously with the increasing of the fractal dimension of slag powder.In addition, it has a certain relationship between the fractal dimension of slag and the activation of pozzolanic activity of slag in cement. It can be drawn from the microstructure image of SEM in 3 day: when the slag fractal dimension is more than 2.47, the content of C-S-H and AFt increased obviously of cement stone in early day, the early strength of slag cement improved rapidly at the same time.更多还原