氧化铝微粉对铝酸钙水泥结合浇注料的施工性能和力学性能的影响

发布时间：2018-03-15 01:13

本文选题：铝酸钙水泥　切入点：氧化铝微粉　出处：《郑州大学》2017年硕士论文　论文类型：学位论文

【摘要】：已有研究发现氧化铝微粉会对铝酸钙水泥的水化有较大的影响。铝酸钙水泥结合浇注料的性能与铝酸钙水泥的水化紧密相关,但目前还没有关于不同商品氧化铝微粉影响铝酸钙水泥结合浇注料的水化、施工性能和力学性能的系统研究。本研究中选取了粒度有较大差异的四种氧化铝微粉。在常温下,研究了这四种氧化铝微粉对铝酸钙水泥的水化,浇注料的流动度、流变性、铝酸钙水泥结合浇注料基质的水化和脱模强度,以及浇注料烧后强度的影响。实验结果发现:(1)氧化铝微粉促进了铝酸钙水泥水化和水泥结合浇注料基质的水化,因而氧化铝微粉对铝酸钙水泥水化的促进作用加速了浇注料流动性的衰减。(2)不同粒度的氧化铝微粉对浇注料的流变行为有不同的影响。添加3%-7%的氧化铝微粉A和C均使浇注料基质试样在相对较短的时间内达到流变仪的最大扭矩,说明在所测试的60min内,添加3%-7%氧化铝微粉A和C的浇注料基质中,铝酸钙水泥的水化都比较快。在0-60min之间,氧化铝微粉B和D的添加对浇注料基质扭矩随搅拌时间的影响相近。这一结果表明粒度较小的微粉A和C都加快了水泥在基质中的水化速度,而粒度相对较大的微粉B和D的添加对浇注料基质的影响不大。(3)不同粒度的氧化铝微粉对浇注料的脱模强度有不同的影响。添加粒度较小的氧化铝微粉A和C的浇注料试样的脱模强度要高于添加粒度较大氧化铝微粉B和D的浇注料试样。这是因为较小粒度的微粉能更好的填充浇注料颗粒和细粉间孔隙,使浇注料有较高的密度;同时,较细的微粉能更大程度上促进浇注料基质中水泥的水化速度。(4)浇注料经1450℃热处理后,不同粒度的氧化铝微粉对浇注料强度的影响的最佳加入量不同。当较细的氧化铝微粉的加入量为5%时,浇注料的强度最高;而较粗的氧化铝微粉加入量为7%时,浇注料强度最高,这是因为不同粒度的氧化铝微粉对片状CA6的生成和长大的影响不同。
[Abstract]:It has been found that alumina powder has great influence on the hydration of calcium aluminate cement. The properties of calcium aluminate cement binder are closely related to the hydration of calcium aluminate cement. However, there is no systematic study on the effect of different commercial alumina powder on hydration, construction performance and mechanical properties of calcium aluminate cement binder. In this study, four kinds of alumina powder with different particle size are selected. The hydration of calcium aluminate cement, fluidity and rheology of castable, hydration and demoulding strength of calcium aluminate cement matrix were studied. The experimental results show that the Al _ 2O _ 3 micro-powder can promote the hydration of calcium aluminate cement and the hydration of cement-bonded castable matrix. Therefore, the promoting effect of alumina powder on hydration of calcium aluminate cement accelerates the fluidity attenuation of castable. (2) different sizes of alumina micro-powder have different influence on rheological behavior of castable. The addition of 3- 7% alumina powder A and Al _ 2O _ 3 micropowder has different influence on rheological behavior of castable. C makes the castable matrix sample reach the maximum torque of rheometer in a relatively short time. The results show that the hydration of calcium aluminate cement is faster in the castable matrix containing 3- 7% alumina powder A and C within 60 min, and the hydration of calcium aluminate cement is between 0 and 60 min. The effect of addition of alumina powder B and D on the torque of castable matrix with stirring time is similar. The results show that the micro-powder A and C with smaller particle size can accelerate the hydration rate of cement in the matrix. However, the addition of B and D with relatively larger particle size has little effect on the matrix of castable.) Alumina micro-powder of different particle size has different influence on the demoulding strength of castable, and the addition of alumina micro-powder A and C with smaller particle size has different influence on the demoulding strength of castable. The demoulding strength of castable sample is higher than that of castable sample with larger alumina micropowder B and D. this is because the smaller particle size micro-powder can better fill the castable particle and the pore between fine powder and castable particle. At the same time, the fine powder can promote the hydration rate of cement in the castable matrix to a greater extent. The optimum addition amount of alumina micropowder on the strength of castable is different. When the addition of fine alumina powder is 5, the strength of castable is the highest, while that of coarse alumina powder is 7. The highest strength of castable is due to the different effects of alumina powder on the formation and growth of flake CA6.
【学位授予单位】：郑州大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TQ172.1

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