In order to solve the retainingroadway roof severe subsidence problems in the mining of HuangBaiCi mine close lower coal seam 1016 face, the paper used theoretical analysis and numerical simulation study upper seam floor failure depth and rock pressure of "left lane" in the process of 1016 face mining. The results showed that, since the distance between two layers of coal is very small, resulting in lower seam roadway self –supporting capacity was low. After 1016 face mining, the auxiliary inlet pressure increased, when it exceed the supporting intensity the roof would happen to sink. Using two DZ28-100 type single pillar to intensive support each row “U” shaped steel shed control the roadway deformation effectively.

To solve the problem of gliding and inclining of the devices and the side falling, the HuaShan Coal Mine uses the reset device of hydraulic support , the non-skid device of conveyor, the defense of the face and the slow transition face arrangement, which solve the stability of the equipments and safety protection of workers. The practice results show that the devices stability controlled well and the production efficiency enhanced.

Abstract: this article is based on the return air alleys of ventilation shaft which gets crushing plate and high confined water special geological conditions in Jin ding mine of Yi colliery .To study the reasons and mechanism of floor heave of roadway, and through the combination of shallow and deep way of grouting to carried out the floor heave of roadway floor management. The results show that the roadway floor away from the Cambrian limestone water is only 39 m, under the influence of the construction drilling in the early stage, the Cambrian limestone water is shallow import floor, the roadway floor heave has happened under the combination of mine pressure and high pressure water. Through the method of combining roadway bottom aquifer of shallow deep and shallow overburden bed separation grouting to reinforce the Cambrian limestone. Through this way to reduce the roadway water inflow and control the floor heave of roadway effectively.

According to the production principle of mine safety and efficiency, based on previous research results,using a combination methods of summary and theoretical analysis, the spatial arrangement of“three equipment matching”in fully-mechanized face was studied. The results showed that: it was a scientific and reasonable matching methods that empirical method was primary, and the theoretical analysis was auxiliary. Finally, based on a selection result of fully-mechanized coal face equipment, it carried out spatial arrangement of “three equipment matching”and ground joint commissioning. It will be provided some value for research in future in reasonable spatial arrangement of “three equipment matching”.

In order to strengthen the flocculation and settlement of coal slurry, a combination of electrochemical and ultrasonic pretreatment method was proposed , turbidness of supernate and sedimentation rate were chosen as evaluation index , the impact of different electrodes, electrolytes, ultrasonic energy density, ultrasonic time on sedimentation efficiency were analyzed. Contact angle meter and image analyzer were used to characterize the slime wettability and floc morphology ultrasound before and after electrochemical treatment, The results showed that: Sono-electrochemical pretreatment could improve the efficiency of coal slurry flocculation and sedimentation, compared with electrochemical pretreatment , supernate turbidity decreased by 5.88NTU and sedimentation rate improved by 2cm / min. The optional Sono-electrochemical conditions of graphite as anode and stainless steel as cathode, magnesium as electrolyte, ultrasonic time of 4min and ultrasonic energy density of 0.5 W / cm3 were obtained.

In this paper, the experimental surface tension, contact angle experiments and experimental study of coal dust settling dust wettability wetting properties and preferred wetting agent. Studies have shown that: Suitable surfactants can greatly improve the wetting properties, distilled water and mine water test results mine water has better wetting properties; nine kinds of surfactants derived comparative tests primaries anionic and non-ionic surfactants the superior performance of cationic wetting agent and a zwitterion surfactant; wetting properties of the surface active agent is not necessarily proportional to the concentration of the surfactant, while the results at 30 ℃ better wetting properties of the surfactant; By wetting contact angle and dust settling tests, the final concentration of 0.35% come fast infiltration T is the optimal wetting agent.

Short circuit protection of high-voltage power lines in coal mine cannot realize selectivity with existing protection systems. To solve this problem, a scheme of protection and monitor underground based on PROFINET was proposed. The system is mainly composed of PROFINET network, monitor, controller, and integrated protector with PROFINET IO interface circuit. The system achieves protection and power monitoring network integration, completes the selectivity of short circuit protection, and can determine fault position quickly. Thus the troubleshooting time is cut and reliability of power supply network is improved. The simulation results show that the POROFINET real-time meets the requirement of protection and the system can realize short-circuit protection and power monitor function.

A slack rope, the rope break accident in the mine in the process of ascension has occurred, the vertical shaft hoisting rope card tank system and anti dropping device braking dynamics, of a mine shaft cage rope, rope breaking deadly accidents are analyzed and calculated.

Due to the impact of internal and external forces, tunnel drilling rig in the working could lead to instability, and affect the safety of the drilling rig work. Tunnel drilling rig could be kept its stability by loading a steady pressure on the base of the drilling rig when it was working. The steady pressure was decided by human experience at present, not be by a theoretical method. This method supported by a study of ZDY320 tunnel drilling rig can calculate the steady pressure of the drilling rig by finding the relationship of the steady pressure with the angle of drilling and the angle of support bar. In this method, the stability simulation analysis of drilling rig under the static and dynamic stimulations was made, and a variation law of drilling rig stability was obtained, which provided a theoretical support for the design of tunnel drilling rig.

Because of the lacking of realistic, the operators which use these systems cannot immerse in the simulation training system. Taking EBH-120 road header as a example, a motion simulation method based on physics engine is figured out. It uses 3ds Max for making 3D models and Newton physics engine for dynamic simulation. A tracked vehicle training system with real physics characteristics was developed based on Quest3D, which can improve the deficiency in coal mine training field.

The steering radius of roadheader has a great infulence on the steering performance in tunnel, so it is of great significance to analyze and investigate the steering radius of roadheader. In this paper, based on the present steering radius model of track, a new computational model of steering radius of roadheader is proposed, in which boundary dimension of roadheader, horizontal swing of cutting arm and steering radius of track are taken into account. And then, the influences of track steering radius and horizontal swing of cutting arm on steering radius of roadheader are analyzed and obtained, the research results provide a reference base for the design of roadheader and assessment of steering.

Surrounding rock control of roadway is one of the inevitable problems in coal mining. The down crossheading of 2505 working face at Hengjian Coal Mine is in a fault zone. According to the field observation, the deformation and failure characteristics of surrounding rock were analyzed, and instability mechanisms were also revealed. The analysis indicates that the main causes of deformation and failure of surrounding rock are that the non-coupling states for the support system and rock mass. In order to solve the problem, a new technique that “bolt + anchor + mesh reinforcement + W-type steel band + channel steel” controlling surrounding rock of mining roadway by using the coupling supporting theory ,and parameter and procedure of supporting were optimized, The site monitoring and observations indicates that the technique has achieved the stability of minding roadway. Key Words: mining roadway; deformation mechanism; bolt-mesh-anchor support; coupling support; control technology?

Describes the occurrence characteristics and the main control methods of gob water，analysis the defects of short distance rotary drilling and the advantages of long-distance directional drilling in gob water exploration. Based on the Specific examples of directional drilling in ground and under the mine in Shenhua Wuhai Coal Group Corporation Limited，describes the technical and economic advantages of directional drilling in small coal mines border and upper erratic gob water exploration. The study can provides a new technical approach in gob water exploration under similar conditions.

In order to solve the support problem of crushed surrounding rock of thick unconsolidated layers in Chensilou mine，based on the geological conditions and supporting types and parameters of -720 level main return air roadway.By using FLAC numerical simulation software.Strengthen the control technology of supporting structure is put forward. anchor performance parameters and supporting scheme are simulation analysis including anchorage length、pre-tightening force、anchor length and space between bolts. Simulation results show that design support scheme is superior to the original support scheme.The practice shows that the support scheme is scientific and reasonable, achieve the expected support target.

In this paper, the author analyzed the cycle of surface pre-grouting, found that unstable of drilling fluid properties and high materials consumption in drilling process were caused by dilution of water, physical, chemical pollution of grouting materials. Put forward proposals to reduce drilling fluid materials consumption from process control, using new materials and management control. Good engineering effects were obtained by using three level control processes.

For large deformation roadways, because of the large amount of roof subsidence and this often leading to anchor rope breakage or support failure, in order to avoid the occurence of roof accidents and repeated reinforcing support, we developed a type of connected long bolt which is suitable for large deformation roof. Connected long bolt which is made up of left-hand thread steel metal rod body, pier coarse rod connector, connecting bolt and bolt tail thread. According to the field test, its overall mechanical properties is the same to the common steel bolt of the same diameter. In Baode Coal Mine, Shendong Coal Group, we did field tests, meanwhile the roof deep basic points displacement monitoring and connected long bolt axial force monitoring of the test roadway was carried out. The monitoring results show that connected long bolt can be synchronous with roof rock deformation, avoiding the roadway roof caving caused by anchor rope breakage because of low anchor cable elongation. Connected long bolt can control roof subsidence deformation of roadway with large deformation better. At the same time, its supporting cost was analyzed, and the result shows that replacing anchor cable with connected long bolt can greatly reduce the reinforcing supporting cost.

With the enlargement of the mining depth and scale of Yuwu coal mine, goaf gas emission has become the main factor of restricting its high yield and efficiency. Based on the phenomenon of current drilling machine which hole depth is not enough and time of gas drainage is short, VLD-1000m directional drilling machine of Australia has been introduced in recent years. A new goaf drainage technology of high level fracture boreholes using this drilling machine has been put forward. The analysis results show that this technology has more advantages than current drilling technology, which are mainly reflected in that the effect of gas drainage is good and the capability of positioning is strong, and which need very small quantities of drill sites and cost. So this technology can govern the problem effectively of goaf gas emission, and has a broad application prospect.

Aiming at to adverse geologic condition and permeability waste area of Nianzigou mine, the paper detailed analysis the topographic features of underground tunnel, shaft location, coal mine industrial site and so on, the exiting problems and optimizing development plan were put, finally inclined shaft development scheme was determined from the technical safety and economic comprehensive comparison. According to field implementation of proof, system optimization is simple, earthwork volume is greatly reduced, the underground tunnel to avoid the influence of bauxitic mudstone, existing facilities are effectively used in industrial fields

For special geological conditions of mudstone in shale surrounding rock through auxiliary inclined shaft of Simingshan coal mine and on the basis of analyzing auxiliary inclined shaft deformation, supporting scheme of pipe-shed grouting, pipe-shed grouting, U-steel ribs support was adopted. The engineering practice shows that the integrity of supporting structure and carrying capacity were effectively improved through the supporting scheme, with ensuring drive speed of the shaft, it also provides the reference of support technology for the similar condition shaft.

Due to the special condition and complexity of the areas such as underground temporary roadway and the coal face, traditional communication methods cannot meet the requirements. Based on IEEE 802.15.4 protocol, this paper proposed the design proposal for one type of portable ad hoc network voice communication system by taking advantages of ZigBee technology, including low power consumption, short time-delay, small volume, strong flexibility and so on. Besides, principle of operation for the proposed system was introduced and field experiments were conducted. The results showed that the designed system can meet the requirements for underground temporary roadway construction and emergency rescue.

In view of the actual demand of emergency rescue process of Zhaolou coal mine safety production, a coal mine emergency rescue management system based on B/S was designed and implemented, which combined with the WebGIS technology, spatial database technology as well as the actual emergency rescue process.The system utilized the SuperMap iServer service management and ThinkPHP framework. The design of coal mine accident emergency rescue process and key technology were introduced,and the overall system requirements, functional design and database design were analyzed in this paper.Finally,the key function of each subsystem were elaborated . At present, the system has been put into use in Zhaolou coal mine,which provides the powerful guarantee for the safe production.

To find out the cause of the floating accident in Fengtaifengyi underground garage project，studies including analysis of the failure mode and on-site surveying are conducted. After the studies， such facts are thought to be the cause of the accident：1.Neglecting the seriousness of water influence， the constructors stopped dewatering too early；2.Backfilling work quality did not meet the requirement of design; 3. Neglecting the seriousness of water influence， supervisors did not function well in supervising the construction process; 4. Neglecting the seriousness of heavy rainfall，no effective measures were taken to drain water away; etc. This paper introduced the emergency measures taken to minimize the loss of life and property, and it also introduced the permanent reinforcement of the damaged structure. After the reinforcement, the structure went through a whole rain season and appeared to be in good condition, from what, we can think that the measures worked as expected, and achieved desired effect.

Abstract：According to the occurrence and mining conditions of 19 # coal seam of Baliancheng , the coal gas sources are analyzed in the process of mining ; according to the characteristics of the gas distribution, the air volume has been determined, and gas disaster has been effectively prevented through to take the technology—play elevation drilling to drainage gas and Set up the Patio in the roadway and buried pipes in the gob—in coal face 21906. In the meantime, the upper and lower tail lanes are applied with the measures such as tail lane filling and pre-split blasting of the roof which can prevent gas accumulation.The accumulated experience of design and construction, for the mine even for the entire Huichun Coal Mining area has a good effect of reference and guidance.

According to the characteristics of coal spontaneous fire in goaf of caving fully mechanized face, such as wide high temperature range and hidden of high temperature point, based on the requirements of coal spontaneous fire, the compound fire prevention technology of multiple oxygen insulation and three-dimensional cooling is put forward, namely in three aspects of reducing air leakage of goaf, reducing the coal surface in contact with air and preventing air into coal porosity to reduce exposure of coal and oxygen, while through embedded piping in the corner, fire prevention borehole before frame and high level borehole , three-phrase foam is injected into goaf to inhibit the oxidation of coal, thus hidden trouble of coal spontaneous fire is achieved to control . This technology was applied at 1303 working face in Guojiahe coal mine, after the implementation the concentration of CO decreased from 540 ppm to 150 ppm, hidden trouble of coal spontaneous fire in goaf was controlled effectively.

Based on the analysis of dust producing characteristics of high wind coalface in Yangquan coal mine, dust composite control technology was used to control the dust in the inlet Lane, crushers, coal face and the return airway. The results showed that the dust control efficiency can reach above 90%, and the working condition in coal mining face was improved effectively.

Hidden danger investigation and governance are the top priority of coal mine enterprise's safety management. With the development of informatization, coal enterprises have accumulated a lot of hidden danger data. How to effectively use these historical data has become a new challenge of current safety informatization construction in coal enterprises. This paper first puts forward the concept of data cube and OLAM architecture, and then proposes Apriori_DataCube algorithm based on the integration of OLAP drill function and inter-dimensional association rule. Secondly, this paper extends support-confidence framework based on Kulczynski. Finally, this paper empirically analyzes the Xuehu mine hidden historical data provided by Microsoft SQL Server integration service platform, which provides a new way for coal mine enterprise to grasp the hidden danger trends timely and enhance the hidden danger investigation and governance ability.

The modern coal chemical industry is a resource-intensive, technology-intensive and investment-intensive industry with relatively high risk. With the adoption of AHP as a tool for analysis and a case study, the article conducts an assessment regarding the different investment risk factors. With the building of an index system for risk assessment, the level and weight of each index are defined and more than that, a further analysis is carried out explaining the reasons behind. Finally the overall risk value is calculated. The result shows that certain risk factors like the micro level project investment returns, the maturity of certain technologies and the lack of professional talents yield greater influence than others. An enterprise could make comparison between the overall risk value and the critical value it has pre-defined so as to provide reference for investment decision-making.

In order to explore a water preserved mining method for Wangjiagou coal mine under the Salawusu FM of Yushen mining area in Northern Shaanxi, taking the geological and mining conditions of the fully-mechanized face 1301 and 1302 as background, basing on the principle of interaction between filling strip and key stratum, using both similar and numerical simulation, a comparative research on law of water flowing fracture development respectively resulting from caving method and strip-filling method is conducted. The results show that, the maximum height of water flowing fractured zone of caving face 1301 is about 110.4m, while that of strip-filling face1302 is about 55.4m. With the periodic failure and instability of immediate roof and main roof as well as the key stratum, water flowing fracture intermittently develops upward at varying velocity. The filling strips support the key stratum and coordinate to its flexural subsidence, effectively control the height of water flowing fractured zone, and thus the purpose of water preserved mining under aquifer of Wangjiagou coal mine is finally achieved.

Coupled process of coal deformation and gas flow has received considerable attention because of its importance in gas outbursts during coal mining. Coal permeability is closed related to its stress state. In this paper, coal permeability in the whole stress-strain process under various gas pressures, was measured for analyzing the effect of gas pressure on coal strength and permeability. Furthermore, some triaxial compression tests under the defined confining stress, not containing methane, were also carried out in order to neglect gas effects. Then according to porous media mechanics, coal porosities under different axial stresses were calculated based on coal stress and strain data of the triaxial compression tests. It is shown that the trends of coal porosity and permeability curves with the same effective confining stress are roughly same. Therefore, under triaxial compression, the effective confining stress has an important effect on the permeability evolution before coal peak strength. The more effective confining stress is given, the more coal permeability before coal peak strength decreases.

Shallow coal seam in west China mining induced deterioration of surface ecosystem. the root of surface diving drains is the instability of water resisting groups caused by mining.The domestic research on water stability of water resisting groups, research has focused on the "Water-flowing Fractured Zone", ignoring the affect of "downward cracks" to the stability of water resisting groups in subsidence basin edge tension band. To protect the shallow diving through a rational design of the back filling mining parameters,this paper researched on mechanical model of "boundary pillar?filling strip?water resisting groups" and established formula of "upward crack" and "downward crack" height, Laid certain theoretical foundation of solving water level drawdown of Sara Wusu group aquifer in north Shanbei jurassic coalfield.

Taking the large inclination coal seam with dip mining stope as the research object of 2317 working face of Geting mine ,by using the method of similar material simulation and theoretical analysis,the movement laws of roof ,the tabscission layer of the overlying strata,immediate roof damage rules and dynamic evolution rules of basic roof structure were studied.The results show that the roof weighting interval is longer when adopt dip mining,which the first weighting interval of basic roof is 50m and the periodic weighting interval is 25m;stope abscission layer as "a acute triangle shape" formed composite structure moves regularly from under a rock; immediate roof is Irregular caving then the caving rock are sliding to face,which is bad for working face and basic roof can become immediate roof when working face is advancing to a certain distance to make position of immediate roof up, basic roof structure obvious movement areas mainly in the inclined upper part,basic roof structure in the vertical strata of breakage and movement is steady,basic rock beams develop to the upper strata along the tendency as a "step".

To explore kinds of similar materials and the materials proportion that suitable for soft rock roof employed in underground coal gasification(UCG) model test, mechanical parameters of soft roof taken form field are obtained by rock mechanics property experiment. Based on similarity principle , river sand are selected as aggregate, with clay and gypsum for cement. Some different ratios of materials are made by means of orthogonal experiment and comprehensive experiment, and the uniaxial strength of similar materials are used to make compare with the uniaxial strength processed by similarity principle. The results show that the gypsum can not serve as a cement for soft rock roof used for UCG model experiment, as the gypsum has a significant influence on the strength of similar materials, and is prone to pulverize under high temperature. While river sand and clay are selected as raw materials for making similar materials, and the uniaxial strength of similar materials made at the river sand/clay ratio of 3:1 is consistent with the uniaxial strength by calculated according to similarity principle, and meet the mechanical requirements of soft roof used for the UCG model experiment.

In order to research the emission and distribution about gas in in the production process of fully mechanized top coal caving face in the gas outburst mine, taking the Mount Huangshan +735 coal mining face as engineering background, using the element method to measure in fully mechanized top coal caving face , collecting the data of distribution of gas , and the data collected are analyzed and studied, so got high gas mine approximate "company U+L" type ventilation in fully mechanized caving face under the gas, and along the vertical direction, coal mining face wall direction gas distribution, migration, provide certain reference to the coal mining and gas prevention occurrence in similarly conditions .

Due to a variety of electrical equipment using, the grid power quality severely polluted. For current harmonic signal mine hoist converter generates, the methods is proposed based on Hilbert-Huang Transform (HHT) to detect current harmonic signal and improved Active Power Filter. The simulation mode Established by MATLAB / Simulink software about shunt APF+SPWM inverter hybrid active filter device for harmonic motion detection and suppression simulation. The results show that this design method can detect harmonic of hoist converter real-time and compensate the system current , and also can suppress harmonic validly.

Changes in lighting conditions will affect the work efficiency of sub-surface mining. This paper analyzes the mean of minimum illumination level for the coal mine drilling workers and determines the value of optimum lighting level by experiment; through the LED multi-light-source theoretical analysis and the TracePro numerical simulation analysis, it finally determines the optimized number of the LED miner cap lamp bulbs and their arrangement, providing reference for the miner cap lamp design.

Dense medium cyclone is a widely used and high effective coal preparation equipment and the force on particle in dense medium cyclone is very complicated. Based on the research results of multiphase flow and discrete material, this paper analyzes the force on particle inside DMC. Based on the diffidence between radial and axial flow field distribution inside DMC, the radial and axial motion equation of the particle are analyzed and derived. This paper simulates motion tracks of particle inside dense medium cyclone by using Computational Fluid Dynamics (CFD) and Discrete Element Method (DEM) coupled method.

Based on SOA、WebGIS、javaEE and data exchange technology, a unified dispatching platform for the coal groups is researched and designed to overcome the relatively simple function and problems of data island for existing system. The platform consists of four layers structure, that is presentation layer, business layer, data layer, integration layer. Among which, data integration layer is used to access and integration data, data layer is responsible for establishing data sharing mechanism through the classification storage management, business logic layer achieves specific business logic using the Springmvc framework, presentation layer completes the page implementation and data validation function using SVG, JSP and WebGIS technology. Integrated management portal, platform monitoring, scheduling statistical analysis, Safety supervision networking, personnel positioning networking, production monitoring networking, industrial video monitoring networking, emergency management, information release function, and so on, are realized according to the specific needs of China Coal Energy Group. The practical application proved that the system is stable, reliable, practical and scalable.