固硫灰—钛矿渣复合辅助性胶凝材料对水泥与减水剂相容性的影响

发布时间：2018-04-29 15:40

本文选题：固硫灰-钛矿渣 + 水泥　；参考：《西南科技大学》2015年硕士论文

【摘要】：混凝土的组分越来越复杂,导致复合胶凝材料体系与高效减水剂的相容性问题成为影响混凝土施工性能最重要的因素。其中,劣质辅助性胶凝材料对水泥与高效减水剂之间相容性的影响较大。固硫灰、钛矿渣均属于亟待利用的低等级辅助性胶凝材料,故本课题针对固硫灰-钛矿渣复合辅助性胶凝材料对水泥与高效减水剂之间相容性的影响进行了研究。试验研究选用了聚羧酸系及萘系两种高效减水剂。首先通过Marsh筒净浆测试法,研究了固硫灰/钛矿渣比值及固硫灰细度变化对水泥与减水剂相容性的影响。接着对Marsh筒法研究结果进行了定量评价。最后,从减水剂吸附特性、浆体Zeta电位、凝结时间及流变-触变性等角度探究了固硫灰-钛矿渣影响水泥与减水剂相容性的机理。结果显示,随着固硫灰-钛矿渣比值增加,一方面,提高复合胶凝材料对减水剂的消耗量和浆体水化速率,使浆体饱和掺量、经时损失率及泌水点增加。另一方面,固硫灰-钛矿渣比值增加时,因增加浆体屈服应力和塑性粘度,而延长浆体的初始Marsh时间。粉磨过程减小了固硫灰的颗粒粒径,破坏了其孔结构,且增加了颗粒比表面积。故随着固硫灰细度降低,复合胶凝材料体系对减水剂的吸附量、浆体屈服应力及塑性粘度均降低,使浆体Marsh时间、饱和掺量、经时损失及泌水点均减小。聚羧酸减水剂对复合胶凝材料体系的分散及维持流动性的作用较萘系减水剂强,即便萘系减水剂可明显提高浆体的Zeta电位值。相容性定量分析与定性实验结果匹配度较高,且分析结果说明聚羧酸减水剂对水泥浆体的作用效果受固硫灰掺量的影响较大,而萘系减水剂的作用效果受固硫灰细度影响较大。通过本课题的研究,作者建议当复合胶凝材料体系中固硫灰／钛矿渣比值低于1时选用聚羧酸系减水剂；比值较高时适宜选用萘系减水剂。固硫灰、钛矿渣虽为固体废弃物,但两者复合后能起到取长补短的作用,可较好地应用于水泥体系。
[Abstract]:As the composition of concrete becomes more and more complex, the compatibility of composite cementitious material system and superplasticizer becomes the most important factor that affects the construction performance of concrete. Among them, inferior auxiliary cementing materials have great influence on the compatibility between cement and superplasticizer. Sulfur fixation ash and titanium slag are all low grade auxiliary cementitious materials which need to be used urgently. Therefore, the effect of sulfur fixation ash and titanium slag composite auxiliary cementitious material on the compatibility of cement and superplasticizer is studied in this paper. Two kinds of superplasticizer, polycarboxylic acid and naphthalene, were used in the experiment. The influence of the ratio of fixed sulfur ash to titanium slag and the fineness of fixed sulfur ash on the compatibility of cement and superplasticizer was studied by means of Marsh cylinder slurry test. Then the results of Marsh tube method are evaluated quantitatively. Finally, the mechanism of the influence of sulfur fixation ash and titanium slag on the compatibility of cement and superplasticizer was investigated from the aspects of water reducing agent adsorption characteristics, slurry Zeta potential, setting time and rheological thixotropy. The results show that with the increase of the ratio of sulfur fixation ash to titanium slag, on the one hand, the consumption of superplasticizer and the rate of slurry hydration are increased, so that the saturated content of slurry, the loss rate and bleeding point are increased. On the other hand, when the ratio of sulfur fixation ash to titanium slag increases, the initial Marsh time of the slurry is prolonged by increasing the yield stress and plastic viscosity of the slurry. The grinding process reduces the particle size, destroys the pore structure and increases the particle specific surface area. Therefore, with the decrease of the fineness of sulfur fixation ash, the amount of water reducer, the yield stress and the plastic viscosity of the composite cementitious material system are all decreased, so that the Marsh time, saturated content, time loss and bleeding point of the slurry are reduced. Polycarboxylic acid superplasticizer has stronger effect on dispersing and maintaining fluidity of composite cementitious material system than naphthalene water reducer even though naphthalene water reducer can obviously increase the Zeta potential of slurry. The results of compatibility quantitative analysis and qualitative experiment show that the effect of polycarboxylic acid superplasticizer on cement paste is greatly affected by the amount of sulfur fixation ash, while the effect of naphthalene water reducing agent is greatly affected by the fineness of fixed sulfur ash. The author suggests that polycarboxylic acid superplasticizer should be used when the ratio of sulfur fixation ash to titanium slag is lower than 1 and the naphthalene series water reducer should be used when the ratio is high. Although sulfur fixation ash and titanium slag are solid wastes, they can make up for each other's weakness and can be used in cement system.
【学位授予单位】：西南科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TQ172.1;TU528.042.2

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