In order to excavate coal resourses which is under buildings, water bodies, railways and above confined water, a complete technology of new pumping paste comprehensive mechanization mining technique which is safety, high efficiency, high mining rate and environmental protection has been formed, the study on filling material is very important. In this thesis, the uniform experiment is used comprehensively on the proportioning test of mine solid waste such as coal gangue, fly ash etc. The results showed: (1) the collapsed slump of paste will increase obviously with the increase of the content of fly ash; (2) the paste stratified degree will decrease regularly with the increase of the content of fly ash; (3) the paste bleeding rate will reduce obviously with the increase of the content of fly ash; (4) the paste strength will increase gradually with the the increase of cementing material; (5) early strength agent can improve the early strength of filling test blocks to some extent, but the later strength growth is not obvious.
Based on present situation that coal mining under buildings, water bodies and railways, and solid wastes mainly including coal waste, fly ash in coal mine of our country, optimization proportioning of paste filling material and hydration reaction mechanism is systematicaly researched combining with project practice of paste filling in Daizhuang Coal Mine, Zibo Mining Group. The result shows that: Proportioning design P10 can be used as the optimal proportion results, the rate of cementing material is that the proportion: fly ash: coal waste is 1:4:6, quantity concentration is 74%; Coal waste paste XRD diffraction patterns of different instar shows that its hydration products at different instar stage are mainly gelation of CH, Aft and C-S-H; Relative content of each material in hydration products is different at different instar stage; With scanning electron microscope a certin ettringite is producted after coal waste paste hydrated 8h, and content of C-S-H gelation and CH gelation is increased gradually; Hydration process of portland cement is speed up and the strength of paste is enhanced.
Aiming at the present situation of surface construction damage and pollution by coal mining, introduced the application situation of filling mining technology. In view of China's municipal solid waste present situation, proposed the bag filling mode in coal mine gobs, and put forward the reasonable filling process and filling system design. It is more helpful to deal with the city garbage on a large scale by combining the garbage stowing with the treatment of mine gobs than traditional waste disposal methods, such as burying, compost piling and burning also can effectively control the surface subsidence issues, and it is very significant to science and environment.
The paper sets up mechanical model according to the characteristics of paste filling stope and determines the basic model units which are overlying strata, filling body, support and floor. The paper also establishes the mechanical parameters for controlling movement and deformation of overlying strata and sets up the relationship of all mechanical parameters. Based on this, the paper studies the stress evolution law under the condition of different filling ratio and filling step distance with the method of numerical simulation.
This paper is based on Point-electrode model of electric field of steady current in sea, and regards the seawater as lining,uniformity and apiece-direction congenialitily half-infinity conductor space. Founding on the comparability of steady current field and static current field,the paper calculates the distribution of circle-electrode's electric potential of the steady current in the three-layers medium(air-sea water-seabed) by image method and gets the expession. Thus the paper takes the model of the circle-electrode's electric field of steady current of in the sea .
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