| As the nation carried out the oriented policy of filling method and thoroughly applied the green mine, filling mining was becoming increasingly wider. "To develop green mining, realized least destroying, Develop less waste technology, maximally reduced waste generation" which had become the main direction of innovation. Waste rock and tailing were bulk solid waste and output stability, mine solid waste filling was the most effective way to solve waste emission and support green mining, and the main support technology of green mining. It is the key to the safe highly effective green mining technology about deep mineral resources, which realized the pipeline gravity transportation of high-density filling added with waste rock-tailing. It is more complex than tailing paste or high density slurry, has more influential elements and not easy to control, therefore it was necessary to make further research on the rheological properties and rheological parameter of slurry.The paper based on "Natural Science Foundation of China" and "Major Science and Technology Projects of Gansu Province", Through the analysis and discussion about present situation of filling, made the material of Jinchuan mine and Dahongshan copper mine as the research object, made the experiments of high-density, high-floating and rheology, analyzed the influence factors of rheological properties in detail, put forward the viscosity and yield stress calculation model of high-density filling added with coarse aggregate. At the same time made pipeline test of high-density filling slurry, eventually applied theoretical results to mining filling process. The mainly contributions of this thesis included the following aspects.(1) Combined with application status and the design of underground mine about high density filling, aiming at the inconsistency of definition about high-density, discussed the characteristics of high-density slurry, gave the measure results of slump and collapsed slump, obtained the high-density range under gravity. At the same time put forward the criterion of high density added with coarse aggregate, the criterion had been validated through the slurry of waste rock-backfilling.(2) In the paper used RheoCAD rheometer to make 340 groups rheological experiments, got rheological curve of waste rock-(backfilling) classified tailings and gobi sand-rod-mill tailings. In turn, presented a unified analysis of viscosity-shear rate and shear stress-shear rate curve starting from the change mechanism of slurry, results showed that there existed a breakpoint of viscosity curve corresponding to the shear stress change, got theory basis of analyzing rheological curve about high-density slurry added with coarse sand, got the slurry rheological parameters, which laid a foundation for rheological characteristics analysis.(3) Response surface method was used to analyze particle size, the composition of aggregate, aggregate ratio, as well as the influence of fine fraction content on viscosity. Get taxis of each influence factor about the viscosity of waste rock-classified backfilling using response surface analysis:mass concentration>cement content>ratio, the interactions between cement content and mass concentration was also very significant. At the same time analyzed the influence factors of different materials (mass concentration, cement content, ratio, and fine fraction content in aggregate), the analysis showed that mass concentration and fine fraction content had great influences on the viscosity, cement content came second, the interactions of mass concentration and cement content, as well as cement content and fine fraction content had a significant effect on viscosity. Cement content had bigger influence on the viscosity for different size of gobi sand, granularity change came second, the interactions of mass concentration and cement content, as well as mass concentration and granularity had a significant effect on viscosity. Analyzed the influencing factors of yield stress about waste rock-classified backfilling, the waste rock-tailing,-12 mm～-20 mm gobi sand using the grey relation theory respectively, results showed that cement content and mass concentration was the key determinant of yield stress, the analysis showed that the influent of ratio on the yield stress was smaller, the influence of grain structure change on the yield stress was larger, the second was mass concentration, and the third was the cement content.(4) By analyzing the main influence factors (slurry density and the content of fine particles in the aggregate) found that viscosity was mainly affected by fine fraction content (cement content) and the density of slurry, viscosity has certain quantitative relation with fine grained content and the volume of aggregate, at the same time put forward the two key parameters k1, k2 which related with cement content, viscosity calculation model was deduced according to the factors affecting the experimental data of jinchuan mining gobi sand. The experimental results that relative error was less than 15%, this model had good adaptability, had been validated through the different materials of different mining and other mine backfilling, results showed that the parameters of viscosity calculation model are easy to measure, the error was small, meet the demand of industrial field.(5) Through analyzing the influence factor of yield stress found that the concentration of the slurry and cement content had the main influence on the yield stress, existed index relationship between aggregate volume concentration and the yield stress, and negative power relationship between W/C and yield stress, in combination with other factors, yield stress prediction model was established, and provided the basis for subsequent pipeline resistance calculation.(6) Gambit was used to establish 3D pipeline models according to the actual filling line in Jinchuan and Dahongshan, performed numerical simulations in the solver of Fluent (3D) under the characteristics of slurry and the structure flow theory. At the same time verified the results of numerical simulation through the slump test and actual resistance monitoring of mine, the results showed that the pipeline simulation of high-density slurry with wasterock-tailing was feasible, It verified the accuracy of rheological parameter which obtained from rheological mode, the result provided a theoretical basis for applying high density filling with waste rock-tailing, it has important significance for popularization and application widely.
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