Used numerical simulation method to study the floor water-inrush mechanism in working face which was influenced by fault structure, and set up many kinds of models and performs numerical calculation by fully using large finite element soft-ANSYS and element birth-death method. The results show that the more high the underground water pressure, the more big the floor displacement and possibility of water-inrush; the floor which has fault structure is more prone to water-inrush than the floor which not has fault structure, the floor which has multi-groups cracks is more prone to water-inrush than the floor which has single-group cracks. The numerical simulation result forecasts the water-inrush in working face preferably.
Under the mining influence, carried on the electron microscope, the thin section analysis and creep tests to the fault matter＇s original sample and five groups of duplication samples, which have three kinds of moisture. The results of those tests indicate that confining pressure effect, structure effect and moisture effect all have influence to fault matter＇s nature. Meanwhile, the distortion destruction and stability variation of fault crush zone are the main reason which causes water-inrush lag-effect. Simultaneously, the stimulation computation we made by the numerical simulation software FLAC 3D also describes the mining influence to floor strata, fault crush zone＇s range and size, the influence of confined water on overburden and the fault zones, also it describes the time effect of bearing influenced by confined water and the rock dank height of confined water along the fault zones influenced by the specific water head.
Studied the principle of transient electromagnetic method in coalmine and solved the computation of the whole time apparent resistivity and the relation between apparent resistivity and exploration depth and so on. Studied the work method of transient electromagnetic method in coalmine and obtained reasonable arrangement way. Studied data processing and explanation method of transient electromagnetic method and obtained high quality electric section. Finally the purpose to detect water-bearing body and water-bearing structure in front of roadway in advance, and detect the water-bearing property of the roof and floor rock layer of coal face were realized by use of transient electromagnetic method.
This paper took the abnormal geological objects with high or low resistivity in the coal face as the background to establish the physical model. 2D forward numerical simulation for electromagnetic wave equation was implemented by the finite-difference scheme. According to the simulative results, the attenuation-absorption coefficient were calculated respectively based on field intensity and frequency shift parameter. Research result indicates, when coal-bed contains high electric resistivity geological abnormal object or low electric resistivity geological abnormal object, absorption attenuation function researched by frequency shift parameter of electromagnetic wave signal is more sensitive than by electromagnetic field intensity parameter.
Analyzed roof rock layer structure and rock layer thickness of -550 level west main roadway and proposed that the stability of calcareous rock layer was the premise of mining successfully. According to different roof condition and rock pillar size of main roadway, different reinforcement plans were used to strengthen the stability of rock layer. By studying the influence rule and influence scope of dynamic pressure of main roadway wall rock because of fully mechanized coal face extracting, that the size of rock pillar was the key of affecting wall rock distorting was proposed. Scientific basis was provided for determining the size of reasonable rock pillar, selecting reasonable extracting support plan and reinforcement measures under different wall rock conditions.
