Given that the conventional back propagation neural network (BPNN) easily falls into local optimal solutions, resulting in poor prediction accuracy, an improved BPNN based on differential evolution and grey wolf optimizer (DEGWO) is proposed, so-called DEGWO-BPNN. The of water-conducting fracture zone (WCFZ) height significant for mine safety operations. A total 104 sample data are trained 25 tested to identify model. Five evaluation indexes selected assess performance models quantitatively....

The main purpose of this research is to apply the logistic regression (LR) model, support vector machine (SVM) model based on radial basis function, random forest (RF) and coupled whale optimization algorithm (WOA) genetic (GA) with RF, make landslide susceptibility mapping for Ankang City Shaanxi Province, China. To end, a inventory map consisting 4278 identified landslides randomly divided into training test in ratio 7 : 3. 15 influencing factors are selected as follows: slope aspect,...

Abstract This study presents a case of weakly consolidated strata developed in Dananhu No.7 coal mine. Using combination numerical simulation, field measurement comparison, and the critical hydraulic gradient criterion, we investigate overburden failure risk possibility water–sand mixture inrush during excavation. The following are principal findings: (1) Weakly rocks have poor physical characteristics, particularly when they mudded disintegrated after encountering water, which may become...

With the high-intensity mining activities and selection of interval methods, a large amount high-rank coal resources are left in underground space (isolated islands). However, due to complicated geological conditions, isolated islands have not been fully extracted. In this paper, mechanism water inrush from limestone aquifers under island panels is discussed theoretical mechanics analysis, numerical simulation, discriminant criterion, variation law surrounding rock stress pressure, floor...

This study aims to accurately identify mine water sources and reduce the hazards caused by inrush accidents in coal mines. Taking Gubei as an example, quality results of samples from Cenozoic unconsolidated aquifer, Permian sandstone fracture Carboniferous Taiyuan Formation limestone karst aquifer area were tested, K

Abstract Landslides caused countless economic and casualty losses in China, especially mountainous hilly areas. Landslide susceptibility mapping is an important approach tool for landslide disaster prevention control. This study presents a assessment using frequency ratio (FR) index of entropy (IOE) models within geographical information system She County the region South Anhui, China. First, locations were ascertained area historical records, aerial photographs, multiple field surveys. In...

With the large-scale mining of deeply buried coal seams, risk roof water inrush increases during mining. In order to ensure safe mining, it is necessary predict potential from aquifer. This study introduces a coupling evaluation method, including analytic hierarchy process (AHP), principal component analysis (PCA), and improved Game theory (IGT). paper takes aquifer 11-2 seam in Kouzidong mine as research object. An index system constructed by selecting six factors, aquitard effective...

Fully mechanized top-coal caving mining with high height, hard roofs and strong pressure are popular in the Shendong area, China. The occurrence of dynamic disasters, such as rock burst, coal gas outburst, mine earthquakes goaf hurricanes during exploitation process under roof conditions, pose a threat to safe production mines. In this study, characteristics overburden fracture fully height studied, technology advanced weakening by staged fracturing was proposed. results show that strata...

Water inrush disaster is one of the major disasters affecting production safety coal mines following roof caving, fire, gas outburst, and dust explosion disasters. It urgent to reveal water mechanism take effective measures prevent More than 80% accidents occur around geological structural zones such as faults karst collapse columns (KCCs). The events from KCCs caused huge economic losses heavy casualties, process often shows certain hysteresis characteristics. Taking a KCC during roadway...

The coal-forming period is mainly Permian and Carboniferous in the North China coalfield, which one of main coal accumulating areas China. It characterized by high rank, abundant reserves, varieties. However, water outburst accidents originating from karst aquifers under seam floor have become a terrible disaster accompany with deep exploited progressively. Water inrush events limestone often occurred during excavation mines. To decrease risk confined ensure mining safe pressure aquifers,...

Abstract Identification of the hydrochemical characteristics groundwater system in mining area and controlling factors water's chemical components is necessary to protect resources. In this study, 80 sets samples were collected from three aquifers Liuzhuang coal mine (northern Anhui Province, China), a total eight indicators selected for quantitative analysis water. Conventional mathematical statistical methods Piper trilinear diagrams show that cations are mainly K+ + Na+ (92.4%), while...

ABSTRACT Considering groundwater from the aquifers overlying bedrock is an important water source for drinking purposes. As such, investigation of its property essential. Based on spatial structure in study area, Cenozoic strata are divided into three groups. The multivariate statistical approaches employed to identify hydrogeochemical processes and hydro-chemical types, inverse modeling applied further validate elucidate process water–rock interaction. results as follows: (1) type upper...

Underground mining safety risk increases with the more complicated geological conditions in deep strata, so coal mines turn to upper limit of shallow seams under Cenozoic strata. Nevertheless, Northern China coalfield are mainly covered by thicker loose sandy layers abundant water. The analysis overburdened strata deformation properties is essential for safe, efficient, and environmentally friendly production. This paper discusses migration through mechanical analysis, numerical physical...

Abstract Due to the presence of hard suspended roof, it cannot collapse naturally after being mined in a large-scale goaf. If roof suddenly destroys without human intervention, would cause serious disasters. In this paper, we discuss mechanisms and applications hydraulic fracturing alleviating potential for catastrophic After crack propagation principle, investigate failure stress characteristics overburden with fracturing, taking mine Dongsheng mining area. The results show that regulated...

Abstract This study introduces a case of weakly consolidated strata developed in Dananhu No.7 mine, and we investigate the overburden failure behaviour risk possibility water-sand mixture inrush during excavation through an approach combining numerical simulation, field measurement comparison criterion critical hydraulic gradient for sand-water outburst into working sites. The following findings consist main conclusions. caving zone is approximately 37.3m with caving-mining ratio 3.55,...

The hydrogeological conditions for the Yuanbaoshan Opencut Coal Mine are rather complex, and total average flow rate from August 1990 to July 1997 is very high at 4.95xl0^mVd. Due large widespread water level decline, some problems which difficult overcome in process of numerical simulation encountered, such as drying up aquifer, movement model boundary, prediction redsidual head. In this paper, a 2-dimensional ground area developed solve these by simulating regional drawdowns during...