Application of Improved Fuzzy-Set Pair Analysis in Mine Water Environmental Quality Evaluation

Mine water is an important water resource, mine water resource is of great significance to realize the sustainable development of economy and society, and the evaluation of water quality is an important link of mine water resource. This paper will be improved in Nemerow index method is applied to the fuzzy-set pair analysis method of composite algorithm, and the water quality evaluation of Kongzhuang Mine in Xuzhou is carried out. Finally, compared with the evaluation results of set pair analysis method and grey clustering method, it is shown that the evaluation results of this method are reasonable and scientific, which can provide reliable basis for the utilization of mine water resources

Research on the Development Features of the Shengquan Minefield Fault Structure in Shandong Province

In order to figure out the complexity of Shengquan Minefield fault structure, the required sample data was reorganized and collected in accordance with the field measurement data and the geological information of the 15th coal layer of the minefield. Firstly, according to the exposure condition of the drilling hole, the rose diagram of the fault direction was drawn after specifically collecting the nature, direction, and height gap and realize the visualization of the fault field measurement data, so the complexity of sectional structure can be initially analyzed. Secondly, the similarity dimension model was built through the box-type covering method in order to count the grid number of the fault trace under each sideline, and then the result was applied to the logarithmic coordinate system. By using the least square method, the slope of the bridging curve and, moreover, the fractal dimension value were achieved. Finally, Sufer was applied to draw the contour map of the fractal dimension value. The research result indicates that, through a series of quantitative analyses, this field can be divided into a simple tectonic area, mid-complex tectonic area, and complex tectonic area. &nbsp

Quantitative evaluation of structural complexity in Shengquan minefield based on improved local linear embedding algorithm

Mine water disaster is closely related to the geological structure of the mine. A scientific evaluation of the complexity of the minefield structure can greatly contribute to mining safety. In this study, we optimized the fault impact index in the study area and proposed an improved local linear embedding (LLE) algorithm by investigating the Shengquan coal mine. We analyzed the fault formation age and connectivity between faults in the study area, combined with topology theory, and based on previous studies. The mechanical properties of faults and the influence of small faults on the strata can be combined to derive a quantitative evaluation model of the structural complexity of mines. Based on the evaluation model, the study area was divided into a simple structural area, a medium structural area, and a complex structural area. By comparing the location of water inrush points in recent years with the three-dimensional high-density electrical exploration of the 21,304 working face, the effectiveness and rationality of structural complexity zoning were determined

Height Prediction and 3D Visualization of Mining-Induced Water-Conducting Fracture Zone in Western Ordos Basin Based on a Multi-Factor Regression Analysis

The mining-induced water-conducting fracture zone (WCFZ) plays a critical role in roof water damage prevention and ecological protection. The measured heights of the WCFZ were collected from 52 working faces or boreholes in the Ordos Basin mining area. Four factors influencing the mining-induced height of the WCFZ, i.e., mining thickness, proportion coefficient of hard rock, working width, and mining depth, were analyzed. The optimal unitary function model of each factor and the height of the WCFZ were obtained through single-factor analysis. The grey correlation method and fuzzy ordered binary comparison method were used to determine the comprehensive weight, and the weighted improved multiple regression model was obtained by combination and iteration. The relative error of the model was basically controlled within 10%. Finally, taking the Qingshuiying Coalfield as an application case, we predicted the mining-induced height of the WCFZ by using the new prediction model. The spatial distribution characteristics of the WCFZ were analyzed by the geographic information system. In addition, Groundwater Modeling System (GMS) software was used to build a 3D structure model of WCFZ height to visualize the spatial distribution rules of the WCFZ. The results showed that the height of the WCFZ can be predicted quantitatively by this new method, and the visualization of the WCFZ can be realized. The proposed method effectively analyzes and predicts the mining-induced height of the WCFZ so that water gushing risks from overlying aquifers can be prevented or mitigated in mines

Height Prediction and 3D Visualization of Mining-Induced Water-Conducting Fracture Zone in Western Ordos Basin Based on a Multi-Factor Regression Analysis

The mining-induced water-conducting fracture zone (WCFZ) plays a critical role in roof water damage prevention and ecological protection. The measured heights of the WCFZ were collected from 52 working faces or boreholes in the Ordos Basin mining area. Four factors influencing the mining-induced height of the WCFZ, i.e., mining thickness, proportion coefficient of hard rock, working width, and mining depth, were analyzed. The optimal unitary function model of each factor and the height of the WCFZ were obtained through single-factor analysis. The grey correlation method and fuzzy ordered binary comparison method were used to determine the comprehensive weight, and the weighted improved multiple regression model was obtained by combination and iteration. The relative error of the model was basically controlled within 10%. Finally, taking the Qingshuiying Coalfield as an application case, we predicted the mining-induced height of the WCFZ by using the new prediction model. The spatial distribution characteristics of the WCFZ were analyzed by the geographic information system. In addition, Groundwater Modeling System (GMS) software was used to build a 3D structure model of WCFZ height to visualize the spatial distribution rules of the WCFZ. The results showed that the height of the WCFZ can be predicted quantitatively by this new method, and the visualization of the WCFZ can be realized. The proposed method effectively analyzes and predicts the mining-induced height of the WCFZ so that water gushing risks from overlying aquifers can be prevented or mitigated in mines

Risk Assessment of Water Inrush of a Coal Seam Floor Based on the Combined Empowerment Method

With the exploitation of the lower coal seams of the Taiyuan Formation, the Ordovician limestone water inrush in the floor became more serious. This paper considers the 162 and 163 mining areas of the Jiangzhuang Coal Mine, in Shandong Province, China. A comprehensive analysis of the geological and hydrogeological conditions of the mining area revealed the following: water pressure and water richness provide the water source and power for the floor water inrush; the thickness of the effective aquifer and the ratio of brittle rock can restrain floor water inrush; fault structures provide water inrush channels; and mining damage is an artificial interference and increases the probability of water inrush. Therefore, six factors: the water pressure of the Ordovician limestone aquifer, water abundance of the Ordovician limestone aquifer, equivalent thickness of effective aquifuge, brittle rock ratio, fracture structure, and mining destruction were selected as the influencing factors on water penetration of the bottom plate, and drawing software was used to establish a mining area map of related factors. The improved fuzzy hierarchical analysis method is more suitable for analyzing multi-objective decisions than the traditional hierarchical analysis method, but the weighting of results is influenced by expert experience. The entropy weight method is data-driven, and the empowerment results are objective. The improved fuzzy analytic hierarchy process and entropy weight method were coupled together, to determine the weight of each factor. The new method is not only data driven, but also takes empirical experience into consideration, making the empowerment results more reasonable. An evaluation of coal floor water inrush was established using MapGIS10.6, which is a general tool-type geographic information system software developed by the China University of Geosciences; and the risk of Ordovician limestone water inrush in the floor of the study area was classified into four levels: dangerous, relatively dangerous, relatively safe, and safe. The whole evaluation process is simple, but the evaluation results have practical importance and are very efficient, providing theoretical support for coal mine water prevention and control engineering

Multifactor Prediction of the Water Richness of Coal Roof Aquifers Based on the Combination Weighting Method and TOPSIS Model: A Case Study in the Changcheng No. 1 Coal Mine

Identifying the water richness of coal roof aquifers is an important and difficult goal of hydrogeological research to prevent and control roof water disasters. To evaluate the water richness of roof sandstone aquifers of the No. 1 coal seam in the Changcheng No. 1 coal mine, a multifactor prediction method based on the fuzzy Delphi analytic hierarchy process (FDAHP), entropy weight method (EWM), sum of squared deviations (SSD), and Technique for Order Preference by Similarity to an Ideal Solution (TOPSIS) was proposed. Multisource geological data, including sandstone thickness, burial depth, lithological composition index, core recovery, fault scale index, fault intersections and endpoint density, and fold fractal dimension, were chosen as the primary indicators for evaluating the water richness of roof sandstone aquifers. The FDAHP and EWM were used to scientifically determine the subjective and objective weight vectors of these seven main factors, and the SSD was used to determine the optimal combination weights based on the objective and subjective weight vectors. On this basis, the water richness index (WRI) model was developed using the TOPSIS method to rank the water richness of samples in the study area. A water richness zoning map was created using the WRI values, revealing three zones: the weak water richness zone, moderate water richness zone, and strong water richness zone. Additionally, the map was refined by incorporating hydrogeologic data collected during mining operations, including pumping tests and actual water inrushes from roadways and working faces. It is believed that the proposed WRI model is effective for predicting the water richness of the roof sandstone aquifers of the No. 1 coal seam in the Changcheng No. 1 coal mine based on the engineering practice data used to validate the WRI model