Laws Of Ground Subsidence Geology Hazards During Coal Mining In Eastern Ningxia Coalfield

The coal mining subsidence is a comprehensive edge research area, involves the prospecting, mining, the engineering geology and the hydrology geology, geo-engineering, measurement, mathematics, mechanics, building structure, etc. Up to now, domestic and foreign researchers who studied on the subsidence which caused to coal mining typical geological disaster have obtained the prominent achievement. Due to the coal mining subsidence geology, the mining method, the hydrology and so on the other factors, rules researching and forecasting on local actual conditions become very difficult. In recent years, technicians and governments all over the world pay great attention to the coal mining subsidence, and also carry out lots of research. Especially 100 years lately, the coal mining subsidence has being developed a branch of learning. It has experienced three periods, the hypothesis and inference, the actual measuring and laws recognizing, and the establishing of the forecast methods and theories and practical applications. The paper summarized former achievements on the study of the coal mining subsidence. Considering the Ningxia coal industry group which is large-scale and state-owned in reality, the paper studied the present situation of Eastern Ningxia coalfield geology hazards, evaluating the harmfulness of the hazards' damage, monitoring dynamic displacement and deformation of the hazards and the theological characteristics, calculating the numerical imitation of coal mining subsidence, developing laws of the subsidence of Eastern Ningxia coalfield and trending prediction, etc, and also giving the scientific methods of preventing and controlling the coal mining subsidence hazards. This article used former results for reference, studied following aspects of questions with emphasis:(1) Present situation of coal mining geology hazards and laws of hazard's dynamic displacement and deformation in Eastern Ningxia coalfield.(2) Studying the laws of numerical imitation of coal mining subsidence in Eastern Ningxia coalfield.(3) Studying the laws of the developing subsidence of Eastern Ningxia coalfieldand trending prediction.(4) Analyzing harmfulness degree of the hazard and evaluating the risk of the hazards' damage.(5) Analyzing stability of the Eastern Ningxia coalfield subsidence and trending prediction.(6) Studying the scientific methods of preventing and controlling the coal mining subsidence hazards.Using the numerical imitation, the theory of medium random, the theory of hazard evaluation, the theory of hazard prediction, the paper indicated the laws of subsidence have the difference when the coalfield changed, at the same time it obtained several achievements as follows.1) The paper reviewed the history of the developing of coal mining subsidence study, analyzing the kinds of the hazards caused by coal mining in Eastern Ningxia coalfield, introducing the geology circumstances, geology tectonic and hydrology condition of the mining areas, studying the hazards caused by coal mining by classifying, giving the methods of monitoring the range of overlying strata of working face damaged by mining and dynamic subsiding, analyzing the subsidence influence to the mining working face by numerical imitation, considering the in creep characteristics of the surface subsidence.2) On consider of present subsidence situation caused by coal mining, utilizing numerical imitation method, giving the model and regulation of the imitation calculation.3) The paper found the basic characteristics of coal mining subsidence and deformation, studied the basic laws of subsidence of Eastern Ningxia coalfield.4) On consider of present subsidence situation caused by coal mining, analyzed the degree of the harmfulness caused by the subsidence hazard, and used the evaluating theory to assess the risk of the hazards' damage.5) Found laws of the coal mining subsidence hazard and its developing trend of hazard's stability in Eastern Ningxia coalfield, the paper utilized dividing shape method to predict subsidence trending, confirming the factors that influenced thesubsidence.6) Referencing former practice on preventing and controlling the coal mining subsidence hazards, the article gave the methods on preventing and controlling the coal mining subsidence hazards, confirming how to protect the ecology of the mining area and its principle.