【作者】 曹启坤；

【导师】 张向东； 周梅；

【作者基本信息】 辽宁工程技术大学 ， 岩土工程， 2013， 博士

【摘要】 中国是一个以煤炭为主要能源的发展中国家,在一次性能源消耗中,煤炭占70%以上,并且在今后相当长的一段时期内,中国的能源结构仍将不会改变。人民在享受着煤炭作为能源所带来的利益的同时,也正遭受着煤矸石自燃、堆放以及煤矸石山溃塌等所带来的空气污染、水体污染、占用耕地,甚至导致人民生命财产损失等问题的困扰。本着“物尽其用、就地取材”的原则,论文以自燃煤矸石具有活性及岩性为主线,从基于煤矸石物化性能、自燃煤矸石活化机理、自燃煤矸石水泥活性混合材料、自燃煤矸石轻集料混凝土、自燃煤矸石地质聚合材料、自燃煤矸石固土材料几个方面阐述煤矸石在建材领域综合利用的理论问题与应用技术问题,力求全方位、立体化应用煤矸石。论文主要研究以下几方面内容：(1)通过对自燃煤矸石基本性质的试验,了解辽宁省阜新矿区自燃煤矸石的物理化学特性、矿物组成及力学特性,从而确定自燃煤矸石在水泥、混凝土及路基中资源化利用的可能性。(2)采用机械激活、化学激活相结合的复合方法对自燃煤矸石进行活性激发。基于正交试验设计方法,探讨利用阜新矿区自燃煤矸石制备自燃煤矸石硅酸盐水泥的可行性并给出最佳配合比范围及具体制备方法。(3)利用自燃煤矸石为主要原材料生产21世纪的绿色胶凝材料—地质聚合物,为煤矸石的综合利用提供新的应用领域。主要研究碱激发剂配体对地质聚合物性能的激发作用,通过试验及数理分析优化自燃煤矸石-矿渣-粉煤灰地质聚合物配合比,并验证其胶砂强度等水泥的主要技术性质指标的可靠性。(4)采用人工级配自燃煤矸砂及煤矸石,以自燃煤矸石硅酸盐水泥作为胶凝材料,基于轻集料混凝土配合比设计方法,分别配制不同强度等级的自燃煤矸石粗-细集料的混凝土。并与普通硅酸盐水泥配制的自燃煤矸石集料混凝土进行工作性、强度等对比,探讨并分析煤矸石集料配制的混凝土工作特性和力学性能,研究了大掺量煤矸石在混凝土中应用的可行性。(5)通过石灰-粉煤灰-水泥改良自燃煤矸石混合料作为路基材料,使其成为规模化消纳煤矸石的有效技术途径。首先通过对石灰-粉煤灰改良自燃煤矸石混合料的配合比设计、饱水无侧限抗压强度、击实特性等研究,分析了二灰稳定自燃煤矸石混合料作为路基材料的可能性及强度形成机理。考虑二灰稳定的煤矸石混合料不能很好满足北方地区的抗冻要求。通过不同掺量水泥的对比试验,研究“三灰”稳定自燃煤矸石混合料耐久性性最佳配合比,为工程应用提供了参考,并进行机理分析。(6)利用有限元分析计算方法,在FLAC3D软件平台上,模拟研究不同车载作用下,煤矸石路基沉降变形、塑性区分布、应力分布等特征的变化规律,以此综合分析煤矸石路基的可靠性。得出以下几点主要结论：(1)自燃煤矸石的“质”—富含氧化硅和氧化铝以及“量”—大宗性,使自燃煤矸石与建筑材料在“质”和“量”具有双重近似性,从而决定了自燃煤矸石在水泥、混凝土及固土材料中资源化是实现煤矸石规模化高附加值利用最为有效的技术途径。(2)自燃煤矸石在混凝土和路基材料中应用是可行的。但由于材质特性,存在级配缺陷,需要破碎筛选后才能满足颗粒级配要求；煤矸石与一般的碎石相比,其水稳性较差；通过探讨自燃煤矸石CBR值的试验结果可知红矸石和灰矸石均能满足路用材料的强度要求。(3)对比试验表明煤矸石的活性远高于普通的人工砂,细度对试块强度的影响最大。阜新矿区自燃煤矸石通过机械和化学的激活,可以作为活性混合材料制备煤矸石硅酸盐水泥,当自燃煤矸石：矿渣：石膏：普通硅酸盐水泥为25：10：3：62时,自燃煤矸石硅酸盐水泥的强度达到最大。(4)自燃煤矸石-矿渣-粉煤灰地质聚合物最佳配体：种类为水玻璃和氢氧化钾,比例为1：1。通过二次响应曲面试验及回归分析,确定了水玻璃模数和激发剂掺量与胶砂强度之间的定量关系。水玻璃模数中最优为1.0；激发剂掺量最优为22.6%(占胶凝材料)。(5)将自燃煤矸石硅酸盐水泥、颗粒级配良好的自燃煤矸石粗细集料制备自燃煤矸全集料混凝土,证明了大掺量自燃煤矸石制备混凝土的可行性；通过对比试验及分析得到集料的配比存在“契合效应”,使混凝土的强度得以提高。(6)煤矸石路基混合料的无侧限保水抗压强度满足规范要求,但强度较低不稳定；当水泥掺量达到3%时,水泥改良二灰煤矸石混合料试件的抗冻效果最好。(7)基于FLAC3D数值模拟,通过对沉降变形、应力分布、塑性区分布的变化规律的分析,证明了水泥改良二灰煤矸石路基的优越性。更多还原

【Abstract】 China is a developing country with coal as the main energy, in the primary energy consumption, coal accounts for more than70%, and for a long period of time in the future, the energy structure will not change. With the enjoyment of coal for industrial innovation energy,at the same time, it also suffers from spontaneous combustion of coal gangue, coal gangue dumps and collapse, air pollution, water pollution, the occupation of cultivated land and leads to loss of life and property and other problems.The spirit of "turn material resources to good account, obtain raw material locally" principle, the spontaneous combustion of coal gangue in cement, concrete and subgrade materials used as the main line. Based on the physicochemical properties of coal gangue comprehensive utilization principle, spontaneous combustion of coal gangue activation mechanism, spontaneous combustion of coal gangue cement admixture, spontaneous combustion of coal gangue geological polymer material, spontaneous combustion of Coal Gangue light aggregate concrete, spontaneous combustion of coal gangue soil material aspects of coal gangue comprehensive utilization of building materials in the field of the theory and application of technical problems, to all-round, three-dimensional application of coal gangue. This thesis studies the following aspects:(1) Through the test of basic properties of spontaneous combustion of coal gangue,I get the physical and chemical characteristics of Liaoning Province, Fuxin mining area of spontaneous combustion gangue mineral composition and mechanical properties, then I can determine the possible utilization of spontaneous combustion of coal gangue cement and concrete.(2) The compound method which combines mechanical activation and chemical activation is adopted to carrying out on the spontaneous combustion gangue activity. Based on the orthogonal test design method, I study the using of Fuxin coal mine spontaneous combustion coal gangue preparation feasibility of spontaneous combustion of coal gangue cement and the best mixture ratio and the concrete preparation method.(3) Using coal gangue as the main raw material to produce Green cementitious materials, geological polymer,in21th Century and provide a new application field for the comprehensive utilization of coal gangue. Researching ligand alkali excitation agent on the properties of geopolymer excitation function, through experiments and mathematical analysis optimization of the mix proportioning of the spontaneous combustion coal gangue, slag, fly ash geopolymer, verify the reliability of the indices such as its strength.(4) Using artificial grading of spontaneous combustion gangue sand and coal gangue, with the coal gangue spontaneous combustion Portland cement as the cementing material. Based on lightweight aggregate concrete mix design method, respectively with different strength grade of coal gangue coarse and fine aggregate concrete. And compare Strength and Working performance with common cement of Coal gangue concrete, discussion on the characteristics and mechanical properties of coal gangue concrete, study feasibility of a large amount of coal gangue and its application in concrete.(5) Through lime fly ash cement modified spontaneous combustion coal gangue mixture as roadbed material, make it become effective way to scale consumption of coal gangue. First, by using the lime-fly ash to improve the spontaneous combustion of coal gangue mixture ratio design, full of water and no side limit compression strength, compaction characteristics. Analysis of two ash stabilized combustion coal gangue mixture probability as roadbed materials, and the mechanism of strength. Results show that coal gangue mixture of two ash stability cannot meet the requirements of northern antifreeze. Through the comparative test of different cement content, I give the "three ash" stable spontaneous combustion coal gangue mixture durability of optimum mix, provide reference for engineering application, and analyse its mechanism.(6) As the test data for a sample, according to the result of the test data, the use of finite element analysis and calculation method, the FLAC3D platform, simulation studies under the action of different cars, the gangue subgrade settlement deformation, plastic zone distribution, stress distribution and other characteristics, to the reliability of the comprehensive analysis of coal gangue subgrade.Draw the following main conclusions(1) Spontaneous combustion of coal gangue is rich in silica and alumina and the content of great, the spontaneous combustion of coal gangue and building materials dual approximation in the "quality" and "quantity". So as to determine the spontaneous combustion of coal gangue in cement, concrete and soil materials in the scale of use is the most effective approach.(2) Application of spontaneous combustion of coal gangue in concrete and subgrade materials is feasible:due to the presence of grading defects, need crushing screening can meet the requirements of coal gangue particle gradation; compared with the crushed stone soil, the water stability is poor; through the study of the spontaneous combustion of coal gangue CBR value test result shows red gangue and ash gangue can to meet the strength requirements of road material.(3) Test and analysis shows that:gangue activity is much higher than ordinary artificial sand, the effect of fineness on the strength of test block maximum. Fuxin mine spontaneous combustion gangue can be used as the active preparation of hybrid materials gangue portland cement through the mechanical and chemical activation, when the spontaneous combustion gangue:slag:gypsum:ordinary portland cement=25:10:3:62ordinary portland cement, spontaneous combustion of coal gangue cement strength reached the maximum.(4) Spontaneous combustion of coal gangue and slag-Fly Ash Geopolymer best ligand: types of sodium silicate and potassium hydroxide, ratio of1:1. By quadratic response surface test regression analysis showed that there is a clear quantitative relationship between Sodium silicate modulus and strength inspire agent dosage and mortar. The optimal sodium silicate modulus was1; activator dosage was22.6%(the optimal total cementitious material).(5) The spontaneous combustion of coal gangue thickness of Portland cement, particle size distribution and good spontaneous combustion of coal gangue aggregate preparation of spontaneous combustion gangue concrete, proved the feasibility of large amount of spontaneous combustion of coal gangue concrete; Through the contrast test to get aggregate ratio exists "fit effect", the strength of concrete is significantly improved.(6) The gangue roadbed mixture unconfined water compressive strength to meet the regulatory requirements, but lower strength instability; When the cement content of3%, the best of flyash cement modified gangue mixture specimen.(7) Based on FLAC3D numerical simulation, the variation analysis of subsidence deformation, stress distribution, the distribution of plastic zone, proved in the the flyash cement modified gangue roadbed material is feasible.更多还原