| The mining with filling in goaf is method to resolve the the mining subsidence which is caused by the move of underground rock masses and coal resource recycle at present. This technology can govern the environmental pollution from source which is caused by coal gangue and fly ash accumulation, changes the present of administration after the contamination, and promoting the development of technology from coal mine to environment governing.Rheological property of slurry is the slurry happens deformation and flow under the effect of external shear, and the internal of slurry produces resistance to prevent the deformation and flow. The study of the rheological characteristics of high concentration slurry has real significance for understanding the high concentration slurry’s motion state and change characteristics in the pipe, guiding design of filling engineering system and industrial production, adjusting ratio of filling material, and determining parameters of pipeline transport. This thesis mainly discuss the rheological properties of slurry、pumping characteristics and pipeline transportation technology.Firstly, the physical-chemical properties and mineral composition of coal gangue and fly ash are introduced, the coal gangue’s physical-chemical properties is more stable, so it is suitable to be coarse aggregate of filling materials. The particle diameter which is less than15mm has more proportion in undisturbed coal gangue, so the coal gangue could be screened by vibrating screen for reducing cost. The fly ash’s physical-chemical properties indicate that it possesses pozzolanic activity. It is best considering exciting the activation of fly ash through putting calcium in the filling materials because the fly ash has low calcium and low activity.The thesis studies the effect of concentration of slurry、fly ash content、 fine particle coal gangue content and cement content on the slurry rheological properties. The ICAR rheometer is used in this rheological experiment. Experiment results show that this material’s rheological property conforms to Bingham model. The slurry concentration has high effect on the yield stress of slurry, yield stress and plastic viscosity increase with the increasing of concentration; the fly ash content has different effect on the slurry rheological properties in different concentration; the effect of fine particle coal gangue and cement content on the slurry rheological properties can be attributed to the effect of fine aggregate on the slurry rheological properties.The pumping properties of slurry is studied in the experiment, slump、 slump flow and bleeding ratio were used to testing the influence of fly ash、fine particle coal gangue and cement content on the pumping properties. The experiment show that slurry slump increases with the increase of fly ash when the slurry’s concentration are79%and80%, but this condition is opposite in the81%of slurry concentration. We can see that the concentration has more effect on the pumping properties. The slurry bleeding ratio increases with the increase of fly ash content, so the bleeding ratio has limited to the fly ash. The slump flow shows similar rule with the slump. The content of fine particle coal gangue increases the lubricity and the liquidity of slurry because the its particle feature. Besides, the fine particle could reduce the bleeding for its spaces of particle could keep some water. The cement has less effect on the pumping properties.Lastly, analogue test is used in the experiment which is mainly on the pressure loss of slurry in the pipe. Research results show that the pressure loss shows cyclic change during the pipe pumping process, The higher the frequency of the pumping is, the shorter the cycle is, otherwise, the longer the cycle is; the pressure loss increases as the concentration、velocity and frequency increase, and shows a linear correlation with the velocity of slurry; The flow also shows a linear correlation with the velocity of slurry, which increases with the velocity increases. |
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