煤矿老空区砂土充填材料的试验研究

发布时间：2018-12-28 20:55

【摘要】：煤炭作为我国主要的化石能源,具有开采量大的特点。煤炭的大量开采留下了众多老采空区,给后续生产建设带来了安全隐患。注浆是治理老空区的重要手段,而注浆材料是影响老空区充填方案实施的重要因素,但是现有的煤矿老空区充填材料不能与煤矿老空区充填要求相吻合,所以,研发出新的煤矿老空区充填材料具有现实意义。选取了煤矿老空区充填材料,并分析了所选取材料的特点。其中,惰性材料选用了廉价易得的砂土,胶凝剂选用了水泥和胶固粉,添加剂选用了 FDN减水剂,水取自实验室自来水。并分析了水泥胶结砂土及胶固粉胶结砂土的反应原理。为满足可注性、扩散范围、结石体强度等要求,评价指标选择了流动性、析水率、初终凝时间、28d单轴抗压强度,并对各个指标的取值范围作了分析。试验分先行试验和规律性试验两大步进行,采用正交试验设计。先行试验是在规律性试验前做的一个探索试验,目的是通过广范围的配比摸索出可行的配比区间,为下一步的规律性试验提供参考。规律性试验旨在探索出评价指标与各因素的关系。对试验结果进行了分析,并介绍了在实际施工中,在知道浆材的流动性、析水率、抗压强度的要求后,可根据各个指标汇总后的总图,找到想要的浆材配比。对比了本试验中配制的浆材与以往工程用浆材在成本上的优劣。水泥胶结砂土作为煤矿老空区充填材料,与现有的水泥胶结粉煤灰煤矿老空区充填材料相比,优势不大。胶固粉胶结砂土作为煤矿老空区充填材料,与现有的水泥胶结粉煤灰煤矿老空区充填材料相比,当胶固粉当地生产时,优势很大,其成本不到现有材料的三分之二,经济效益可观。
[Abstract]:As the main fossil energy in China, coal has the characteristics of large exploitation. The large amount of coal mining has left a lot of old goaf, which brings the safety hidden trouble to the subsequent production construction. Grouting is an important means of controlling old goaf, and grouting material is an important factor that affects the implementation of filling scheme in old goaf, but the existing filling material of old goaf in coal mine can not match with the requirement of filling in old goaf of coal mine, so, It is of practical significance to develop a new filling material in old goaf of coal mine. The filling materials in old goaf of coal mine are selected and the characteristics of the selected materials are analyzed. Among them, the inert material is cheap and easily available sand, the gelling agent is cement and cement powder, the additive is FDN water reducing agent, the water is taken from the laboratory tap water. The reaction principle of cement cemented sand and cement powder cemented sand is analyzed. In order to meet the requirements of injectability, diffusion range and stone strength, the fluidity, water evolution rate, initial and final setting time, 28d uniaxial compressive strength were selected for the evaluation index, and the range of values of each index was analyzed. The experiment is divided into two major steps: the first test and the regular test, and the orthogonal design is adopted. The first test is an exploratory test before the regular test. The purpose of the experiment is to find out the feasible matching interval through a wide range of proportioning, and to provide a reference for the next regular test. The regularity test aims to explore the relationship between the evaluation index and various factors. The test results are analyzed, and it is introduced that in actual construction, after knowing the requirements of slurry fluidity, water evolution rate and compressive strength, the desired slurry ratio can be found according to the general plan of each index. The cost of the slurry prepared in this experiment is compared with that of the former one. Cement cemented sand is used as filling material in old goaf of coal mine, which has little advantage compared with existing filling material of coal mine with cement cemented fly ash. As the filling material of old goaf in coal mine, cemented powder cemented sand soil is more advantageous than existing cement cemented fly ash coal mine goaf filling material when it is produced locally, its cost is less than 2/3 of the existing material. Economic benefits are considerable.
【学位授予单位】：煤炭科学研究总院
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TD823.7;TD325.3

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