Analysis And Research Of Ground Deformation By Goaf In Meihe Coal Mine

The development and utilization of underground mineral resources provide thepowerful material guarantee for the social development of our country. As a countrywhich gets a large amount of coal storage, coal resources are widely used in thechemical industry, power industry, metallurgical industry and other fields. With therapid development of economic construction in our country, demand for energy andnatural resources is increasing year by year. However, what is followed is theenvironmental geological problems after mining. There are a lot of geologicaldisasters such as land subsidence, ground fissure in many mines that seriously affectthe local people’s lives and ecological environment.The national infrastructure highlights the problem of the scarcity of landresources. Therefore, many large factories, railway and highway construction shouldbe built above the goaf. It is very probable that the overlying rock of goaf are brokenand collapsed in the external loads, which would affect the stability of foundation andlead to the instability and failure of the building. Therefore, it gets a very important practical significance to do research and analysis of the laws of the ground movementand deformation above the goaf and to research and analysis of the influence of underconstruction loads.In this paper, taking the goaf of Liaoyuan mining (Group) limited liabilitycompany as the research object. Based on going through the domestic and foreignliterature books and the collection of geological data and field survey, to make clearof the research content and the the technical route, wo do analysis and research aboutground movement and deformation problems on the goaf of fourth wells in Meihemine.We get the following conclusions on the basis of the fourth wells’ geological dataanalysis of Meihe coal mine. As the main working bed, No.12coal seam gets thelarge thickness. The characteristics of the coal seam is tilt angle and shallow steep. Ithas been mined for more than20years, land subsidence is almost over and it leads toserious damage at the surface of the study area.Through the analysis of the related data of the goaf, we master the features of theground movement and deformation in the upper goaf mining and then analyzes thelaw of the development and changes.Learn the probability integration method and use it to do theoretical calculations of ground movement and deformation. In accordance with the relevant norms of order,we select the appropriate calculation parameters to calculate sinking deformationvalues, horizontal deformation values, curvature and other indicators.Learn the finite difference numerical simulation software and use the software tosimulate the ground movement and deformation caused by underground mining.According to the analysis of geological data, establish equivalent numericalsimulation model, select the appropriate physical and mechanical parameters and theconstitutive model. When simulation, it sets up a series of monitoring points in thefree surface (top surface) of the model which are used to recorded surface horizontaland vertical displacement during excavation. To solve the problem of large inclinationangle in the study area seam, we do the analysis and descriptions from two aspectswhich are respectively strike direction and dip direction of the seam according to thesimulation results.On the basis of simulating mining has ended, load is applied to the free surfaceof model to simulate the surface movement and deformation under building loads.Respectively, in the center of the goaf,0.05MPa,0.1MPa,0.2MPa and0.4MPaconstruction load is applied. Equivalently, construction load is applied on the offsideand inner side of the goaf. In this case, it simulates the ground movement and deformation under the conditions of different size loads applied at different locations.In this paper, through the contrastive analysis of the the simulation results, we get thelaw and the similarities and differences under different conditions. According to therelationship between the mined "Three Zones " and the foundation depth of influence,it gets the conclusion of qualitative evaluation about foundation stability.