Risk Of Water Inrush Research Articles

Water Inrush Prediction in DongShan Coal Mine Based on GIS and Multi-Source Information

Water inrush in coal mine could be considered as one of the major threats to the security of miners. Thus, it is necessary to forecast the risk of water inrush to ensure the safety of mine production. The mechanism of water inrush and the related factors, such as geological structures, mining pressure, water pressure and water resisting layer are analyzed. The water inrush prediction model was proposed and applied to DongShan coal mine based on GIS and multi-information. Compared with the water inrush status of DongShan coal mine, the results obtained from the water inrush prediction model are satisfied.

Numerical simulation on the risk of roof water inrush in Wuyang Coal Mine

Water-inrush in mine is one of the mine disasters caused by mining. In order to assess the risk of roof water-inrush in Wuyang Coal Mine based on the geological material of the coal mine, we built numerical models for the roof fracture and seepage development rule by using RFPA2D and COMSOL respectively, to analyze the changes in fracture zone, stress, water pressure and seepage vector with the advancement of working face, and compared the results with the field investigated data. The numerical simulation results indicate that: (1) with the advancement of the working faces, the stress relief range and fracture zone in the overlying strata increased rapidly up to about 90m, and then tended to remain constant, reaching a final height of about 95m which agrees with the field investigation; (2) the seepage flow constantly increased with a larger flow volume both in the front and rear area, where the stress concentration are the most serious.

Safety Accident Analysis and Risk Control in Subsea Tunneling

There are more safety risks in subsea tunneling due to the particularity and complexity of its surroundings, so how to control the safety risks effectively has become an urgent problem. Based on the analysis of safety accident cases induced by the subsea tunneling, accident types and corresponding harms are pointed out. By analyzing the engineering characteristics and technical difficulties of the subsea tunnel systematically, the characteristics and occurring mechanism of the safety risk are revealed, and the fact that water inrush is the main safety risk in subsea tunneling is pointed out definitely. Furthermore, the contents of the safety risk control as well as relevant technical system are provided mainly based on water inrush risk, which can be referenced to make control schemes against the safety risk in subsea tunneling.

Comprehensive Assessment of Water Inrush Risk in Deep Mining of Beiminghe Iron Mine

In view of one-sidedness and the limitations in comprehensive evaluation index for water inrush risk, a variety of factors of water inrush induced by deep mining of Beiminghe iron mine are analyzed from hydrogeological characteristics, structural characteristics and mining. Faulted structure, water storage capacity, water pressure, water-resisting layer, miming effect and the change of stress in surrounding rock of two levels of deep mining in mine area are quantized by rock permeability test, field pumping test and finite element numerical analysis. Mathematic model of risk assessment of water inrush in deep mining of Beiminghe iron mine is established by using fuzzy comprehensive evaluation method. Quantitative assessment of water inrush risk is carried out to obtain the value of rank tendency for water inrush risk through that mathematic model.

Prediction of Floor Water Inrush: The Application of GIS-Based AHP Vulnerable Index Method to Donghuantuo Coal Mine, China

Floor water inrush represents a geohazard that can pose significant threat to safe operations for instance in coal mines in China and elsewhere. Its occurrence is controlled by many factors, and the processes are often not amenable to mathematical expressions. To evaluate the water inrush risk, the paper proposes the vulnerability index approach by coupling the analytic hierarchy process (AHP) and geographic information system (GIS). The detailed procedures of using this innovative approach are shown in a case study in China (Donghuantuo Coal Mine). The powerful spatial data analysis functions of GIS was used to establish the thematic layer of each of the six factors that control the water inrush, and the contribution weights of each factor was determined with the AHP method. The established AHP evaluation model was used to determine the threshold value for each risk level with a histogram of the water inrush vulnerability index. As a result, the mine area was divided into five regions with different vulnerability levels which served as general guidelines for the mine operations. The prediction results were further corroborated with the actual mining data, and the evaluation result is satisfactory.

Study and Application of Forecasting System for Water Inrush Under High Pressure in Xiamen Submarine Tunnel Construction Based on GIS

Abstract To ensure the project safety of Xiamen submarine tunnel, it's necessary to study the risk of water inrush under high pressure to provide a reference for prevention and control measures. With the support of GIS software, a forecasting system for water inrush in Xiamen submarine tunnel was researched and developed, which realized the automated process from basic data input to the result assessment of water inrush. The technical route was that the results of numerical simulation have been evaluated by professional model. The findings of the evaluation have been regarded as its background database which has been updated with real-time geological data and groundwater data during the tunnel construction. The forecasting system has been studied by simulation tools of FLAC 3D, MAPGIS as its basic platform and VC++ as the developing tool. System functions include data input and output, data query, water inrush forecasting and result display function. The application of this system in Xiamen submarine tunnel engineering construction indicates that the system can provide a relatively correct engineering guarantee for water detection in safe tunnel excavation.

Assessment Method of Water-inrush Risk Induced by Fault Activation and Its Application Research

Taking water-inrush phenomena caused by the fault activation as the starting point, this article puts forward the concept of water-inrush phenomena caused by the fault activation. And then, based on the catastrophe theory, a mathematical model of this nonlinear dynamic phenomenon is set up. Through analyzing the geological factors, fault parameters and mining factors, combined with the fault activation water-inrush sample database caused by the fault activation, the evaluation index system of water-inrush risk induced by the fault activation is constructed, which could be used to predict the risk of water-inrush caused by the fault activation during mining under different conditions. In the end, through the analysis of the trend of water-inrush risk caused by the fault activition under the comprehensive function, the article further optimizes the mining parameters, thus to reduce the probability of water- inrush caused by fault activation.

Xinhe Mine water inrush risk assessment based on quantification theoretical models

Taking the Xinhe mine’s structure, mine pressure, structural fissure, fault and fault displacement, the distance between fault and water inrush point, thickness of block, water pressure those geological factors which influenced the water inrush as the independent variable, based on these data of water inrush point and water uninrush point, using the method of quantification theory(I,II), it would quantitatively disposes the qualitative variable, applied to calculation to evaluate the risk of Xinhe’s water inrush.

Predicting the height of water-flow fractured zone during coal mining under the Xiaolangdi Reservoir

It is very important to determine the extent of the fractured zone through which water can flow before coal mining under the water bodies. This paper deals with methods to obtain information about overburden rock failure and the development of the fractured zone while coal mining in Xin'an Coal Mine. The risk of water inrush in this mine is great because 40% of the mining area is under the Xiaolangdi reservoir. Numerical simulations combined with geophysical methods were used in this paper to obtain the development law of the fractured zone under different mining conditions. The comprehensive geophysical method described in this paper has been demonstrated to accurately predict the height of the water-flow fractured zone. Results from the new model, which created from the results of numerical simulations and field measurements, were successfully used for making decisions in the Xin'an Coal Mine when mining under the Xiaolangdi Reservoir. Industrial scale experiments at the number 11201, 14141 and 14191 working faces were safely carried out. These achievements provide a successful background for the evaluation and application of coal mining under large reservoirs.

Comprehensive evaluation of water-inrush risk from coal floors

Lower groups of coal seams are presently being mined in the Yanzhou coal mining area. We need to evaluate the risk from water-inrush from coal floors in order to have safe production in the lower groups of coal seams in mines. Based on a systematic collection of hydrogeological data and some data from mined working faces in these lower groups, we evaluated the factors affecting water-inrush from coal floors of the area by a method of dimensionless analysis. We obtained the order of the factors affecting water-inrush from coal floors and recalculated data on depths of destroyed floors by multiple linear regression analysis and obtained new empirical formulas. We also analyzed the water-inrush coefficient of mined working faces of the lower groups of coal seams and improved the evaluation standard of the water-inrush coefficient method. Finally, we made a comprehensive evaluation of water-inrush risks from coal floors by using the water-inrush coefficient method and a fuzzy clustering method. The evaluation results provide a solid foundation for preventing and controlling the damage caused by water of an Ordovician limestone aquifer in the lower group of coal seams in the mines of Yanzhou. It provides also important guidelines for lower groups of coal seams in other coal mines.

Forecasting water disaster for a coal mine under the Xiaolangdi reservoir

Xin'an coal mine, Henan Province, faces the risk of water inrush because 40% of the area of the coal mine is under the surface water of the Xiaolangdi reservoir. To forecast water disaster, an effective aquifuge and a limit of water infiltration were determined by rock-phase analysis and long term observations of surface water and groundwater. By field monitoring, as well as physical and numerical simulation experiments, we obtained data reflecting different heights of a water flow fractured zone (WFFZ) under different mining conditions, derived a formula to calculate this height and built a forecasting model with the aid of GIS. On the basis of these activities, the coal mine area was classified into three sub-areas with different potential of water inrush. In the end, our research results have been applied in and verified by industrial mining experiments at three working faces and we were able to present a successful example of coal mining under a large reservoir.

Prediction of groundwater inrush into coal mines from aquifers underlying the coal seams in China: application of vulnerability index method to Zhangcun Coal Mine, China

Groundwater inrush is a geohazard that can significantly impact safe operations of the coal mines in China. Its occurrence is controlled by many factors and processes are often not amenable to mathematical expressions. To evaluate the water inrush risk, Professor Wu and his colleagues have proposed the vulnerability index approach by coupling the artificial neural network (ANN) and geographic information system (GIS). The detailed procedures of using this innovative approach are shown in a case study. Firstly, the powerful spatial data analysis functions of GIS was used to establish the thematic layer of each of the main factors that control the water inrush, and then to choose the training sample on the thematic layer with the ANN-BP Arithmetic. Secondly, the ANN evaluation model of the water inrush was established to determine the threshold value for each risk level with a histogram of the water inrush vulnerability index. As a result, the mine area was divided into four regions with different vulnerability levels and they served as the general guidelines for the mine operations.

Application of quantification theory in risk assessment of mine flooding

Abstract Hundreds of mine flooding accidents have occurred in China since the 1950s. These flooding accidents result in submerged working faces, even entire coal mines, leading to tremendous economic losses. It is reported that among 601 state-owned mines in China, 285 mines are exposed to water-inrush risks. The water pressure is becoming larger and larger with the increase of mining depth, leading to an increase of water-inrush hazards. Only when the risk of mine flooding is predicted in a reasonable manner, can we take timely and effective measures to prevent mine flooding from taking place. In our investigation quantification(II) theory is used to study the risk prediction problem about mine flooding. By investigating the main factors which affect mine flooding, eight risk assessment items have been identified. The extent of risk is classified into 4 grades. Given the data from different periods in the Feicheng mining area, a prediction model for the risk of mine flooding is established. The test analysis indicates a model correlation coefficient of 0.97 and the incidence of discrimination is as high as 97.37%, which implies that the effect of the model is quite satisfactory. With the help of computers, this method can be widely applied.

Prediction of groundwater inrush into coal mines from aquifers underlying the coal seams in China: vulnerability index method and its construction

Groundwater inrushes often occur in the coal mines of China. One of the water sources is the aquifers underlying the coal seams. Because such a water hazard is affected by many factors, data collected from various sources need to be evaluated to predict its occurrence. This paper introduces an innovative approach in which the water inrush risk is represented by the vulnerability index. This method combines the geographic information system and the artificial neural network. The artificial neural network is used to estimate the weight of each factor. Unlike the traditional prediction method in which two controlling factors are often evaluated without regard to their relative importance, this new approach incorporates multi-factors and describes the non-linear dynamical processes.