| Paste filling mining is a substantial part of green mining. It is ideal way to solve environment problem of coal mine minging and urgent need to solve coal mining problem under building. Solid waste paste filling non-village-relocation mining was made up of filling material, filling equipment and technology and ground control theory by filling. Filling quality, filling cost and effect of ground control were determined by paste filling material, which was the kernel of paste filling technology. So, coal mine paste filling materials were researched systemically through lab experiments, theory analyses and field test in thesis, and partial conclusions were obtained.Base on the distortion and destroy law or theory of roof strata in work-face, the early strength requirement of paste filling material was analyzed for ensuring work-face safety and high efficiency mining. It made filling body self-stability and supported immediate roof. When filling body was used for false roof of work-face, the post-strength requirement of paste filling material was analyzed for ensuring false roof stability. Through calculation methods of coal pillar carrying capacity in strip extraction, the post-strength requirement of paste filling material in the longwall interval strip filling method was analyzed for ensuring overlying strata long stability, which was supported by filling body, and calculational formulas of early strength and post-strength were obtained. Fluidity requirements of filling slurry were analyzed for ensuring natural transportation and no pipe clogging, increasing the rate of supporting pit roof and decreasing surface subsidence.A new type cementitious material was invented. It was mainly made up of slag, gypsum and lime. It was filling at the price. Through chemistry analysis methods, such as XRD and SEM, hydration mechanism of SL was researched. Main hydration products were analyzed. They were analyzed that affinity-clay of the SL and better concretion ability with extremely small amount of cementation material.They were researched systemically that physical chemistry character of coal gangue, fly ash and loessial soil. The technic routes were put forward that coal gangue with a great deal of soil and poor quality fly ash for filling raw material. Source of paste filling raw material and solving methods were discussed.Through a lot of lab experiments, the rule of paste filling material strength,slump, bleeding rate, shearing stress, apparent viscosity and affecting factors was researched. Aiming at complex none-line relationship between strength and affecting factors, math model was built through neural network. On the basic of uniaxial and triaxial experimentations, mechanics performance was researched. A method to test the allowable specific pressure of paste filling material was put forward. It was using a smaller steel cylinder to apply pressure to the the top face center of a bigger cubic specimen. The relationship between injected depth and average stress and the failure characteristic of specimen were researched.The main compositions of the paste filling system, the technological process of filling and the evolution of backfilling mining about Taiping coal mine were introduced in detail in the thesis. Combining the practical conditions of Taiping coal mine, the general characteristics requirements of the paste filling materials were put forward. Strata behaviors of filling work-face, filling body quality and surface subsidence on the condition of filling mining were observed. The reasons were analyzed that bigger surface subsidence in Taiping coal mine. |
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