铝酸盐基超高水充填材料的制备研究

发布时间：2018-04-30 07:22

本文选题：超高水材料 + 铝酸盐水泥　；参考：《中国矿业大学》2015年硕士论文

【摘要】：超高水材料充填开采是目前广泛应用的一种充填开采方法,所用超高水材料主要为硫铝酸盐基材料,材料来源较为单一。本文以铝酸盐类胶凝材料为基础原料,进行超高水材料研究,以拓展超高水材料的原料来源。通过均匀配方设计研究各主要原料(铝酸盐水泥、石膏、石灰)配比。结果表明:铝酸盐水泥的含量对混合材料有显著的影响,当其含量在50%-90%,石膏和石灰的量大于5%能够达到初凝状态。固定石膏石灰的比例,调节铝酸盐水泥的用量,或固定铝酸盐水泥用量,调节石膏和石灰用量均能达到水固比较高的材料配比。本文对材料的种类及相关影响因素进行了研究,发现:铝酸盐水泥中有效成分、天然石膏种类、石膏粒径分布、水温对混合材料的初凝时间有显著的影响。混合材料中铝酸盐水泥的含量与其有效物质CA和CA2的含量有关。相同条件下,CA和CA2的含量越高,铝酸盐水泥在配比中含量越少。天然石膏中,A石膏比B石膏效果好。石膏粒径分布对材料的混合配比无影响,但对初凝时间有一定影响。石膏粒径越细,混合材料的初凝时间越小。水温越接近环境温度,混合材料的初凝时间越短。本文着重考察了速凝剂对材料初凝时间的影响。通过对28种外加剂筛选比对,发现其中的两种(2号和8号)对混合材料有显著影响,其最佳掺量分别为4%和4.8%。研究表明:外加剂的阴离子半径越小、价态越高,其混合材料的初凝时间越小。同时不同来源的同类外加剂对混合材料的初凝时间有不同的影响,但对最佳掺量无影响。此外,外加剂的掺加方式对混合材料的初凝时间及抗压强度也有显著的影响。通过以上研究,最终制得水固比可达10:1(水体积份额达96%以上)的超高水材料。最佳条件下,在水固比分别为10:1、8:1、6:1时,材料7d强度可分别达到0.19MPa、0.31MPa和0.53MPa,强度上达到超高水材料要求。最后,本文对形成的超高水材料的抗压强度、表观黏度、抗风化性能进行了分析测试。结果表明:形成的材料固结体强度及黏度变化能够满足超高水材料的要求,材料的抗风化性能与硫铝酸盐基超高水材料类似,较易风化。材料固结体具有早强、快硬的特点,1d强度可达最终强度的75%以上。后期抗压强度随时间的增加而增加,但增长速率减小,7d后抗压强度基本稳定。混合材料单浆黏度随水固比及时间变化不大,能够满足工业上对超高水材料管道输送的要求。混浆黏度随时间变化较大。起初,黏度先线性增加,在达到初凝时间时材料黏度瞬间增大。研究表明,用铝酸盐基材料制备超高水材料是可行的。
[Abstract]:Filling mining with ultra-high water material is a kind of filling mining method widely used at present. The superhigh water material used is mainly sulphoaluminate base material, and the material source is relatively single. In this paper, based on aluminate cementitious materials, ultrahigh water materials are studied in order to expand the sources of super high water materials. The proportion of main raw materials (aluminate cement, gypsum, lime) was studied by uniform formula design. The results show that the content of aluminate cement has a significant effect on the mixed material. When the content of aluminate cement is between 50 and 90, the amount of gypsum and lime can reach the initial setting state when the content of gypsum and lime is more than 5%. The ratio of gypsum to lime, the amount of aluminate cement or the amount of aluminate cement, the ratio of gypsum and lime can reach the high ratio of water and solid. In this paper, the kinds of materials and related factors are studied. It is found that the effective composition of aluminate cement, the type of natural gypsum, the size distribution of gypsum and the water temperature have a significant effect on the initial setting time of the mixed material. The content of aluminate cement is related to the contents of CA and CA2. Under the same conditions, the higher the content of CA and CA2, the less the content of aluminate cement in the ratio. A gypsum in natural gypsum is better than B gypsum. The size distribution of gypsum has no effect on the mixing ratio of the material, but it has a certain effect on the initial setting time. The finer the particle size of gypsum, the smaller the initial setting time. The closer the water temperature is to the ambient temperature, the shorter the initial setting time is. In this paper, the effect of accelerator on the initial setting time of materials was investigated. Through the screening and comparison of 28 admixtures, it was found that two of them (No. 2 and No. 8) had a significant effect on the mixed materials, and the optimum admixtures were 4% and 4.8%, respectively. The results show that the smaller the anionic radius and the higher the valence, the smaller the initial setting time of the admixture. At the same time, the same admixtures from different sources have different effects on the initial setting time of the mixed materials, but have no effect on the optimum dosage. In addition, the addition of admixture also has a significant effect on the initial setting time and compressive strength of the mixed material. Through the above research, the super high water material with water solid ratio up to 10: 1 (water volume fraction above 96%) was obtained. Under the optimum conditions, when the water / solid ratio is 10: 1 / 8: 1: 6: 1, the 7d strength of the material can reach 0.19 MPA and 0.53 MPA, respectively, and the strength can reach the requirement of ultra-high water material. Finally, the compressive strength, apparent viscosity and weathering resistance of the ultra-high water materials are analyzed and tested. The results show that the strength and viscosity of the formed materials can meet the requirements of ultra-high water materials, and the weathering resistance of the materials is similar to that of sulphoaluminate based ultra-high water materials, and is easy to be weathered. The strength of the consolidation body is over 75% of the final strength in 1 d due to its early strength and fast hardening. The compressive strength of the later stage increases with the increase of time, but the compressive strength is basically stable after the decrease of the growth rate for 7 days. The single slurry viscosity of the mixed material has little change with the water / solid ratio and time, which can meet the industrial requirements for the pipeline transportation of ultra-high water materials. The viscosity of slurry varies greatly with time. At first, the viscosity increases linearly, and the viscosity increases instantly when the initial setting time is reached. The results show that it is feasible to prepare super-high-water materials from aluminate-based materials.
【学位授予单位】：中国矿业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD823.7

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