CBM combined drainage by up and down well is an important form in coal mine area in China. Firstly, this paper introduces the scientific connotation and realization mode of CBM combined drainage by up and down well, and analyzes the current situation and existing problems, including the combination of coal bed methane development method and construction technology, and the construction technology is divided into with the strip borehole and well drilling, long borehole drilling with underground well, combined fracturing, three-dimensional fracturing, roof fracturing and well with borehole docking. In view of the demand and problem of CBM combined drainage by up and down well, the combined drainage of CBM from the vertical well and the horizontal borehole underground is put forward, and the combination of drainage channel and drainage process is realized. Finally, the prospects for the development of CBM combined drainage by up and down well are presented.

In order to study the effect of in-situ stress on the pressure and permeability of coal reservoir in the Northeast of Pingding Shan mining area , the method of obtaining in-situ stress by hydraulic fracturing is adopted based on the test data of hydraulic fracturing and well test engineering in coal-bed methane wells, the characteristics of in-situ stress development in the northern mining area of Pingdingshan are studied, and the influence of in-situ stress on the pressure and permeability of coal reservoir is analyzed. The study shows that the present in-situ stress field is mainly horizontal stress and belongs to the typical type of tectonic stress field, and the overall stress field is characterized by high dip fault or fracture development; the maximum horizontal principal stress, minimum horizontal principal stress, lateral pressure coefficient and lateral pressure ratio increase linearly with the increase of buried depth.Buried depth is about 682 m geostress type conversion, the geostress type in the vertical transformation is mainly caused by the Pingdingshan mining area multi-stage tectonic movement of the results of stress superposition；The pressure of coal reservoir increases with the increase of minimum horizontal principal stress ，d vertical stress, effective principal stress and principal stress difference. The permeability of coal reservoir decreases with principal stress difference, maximum horizontal effective principal stress and minimum horizontal effective principal stress in negative exponential form.It is the key layout area for coal bed gas fracturing and other reservoir reconstruction and underground coal seam permeability increasing and pressure relief engineering.

Based on the development data of coalbed methane in northeastern Qinshui coalfield,the physical properties and characteristics of No.15 coal reservoir in the study area were analyzed using the theory of coalbed methane geology and mathematical statistics.The results show that the stable and recoverable coal seam provides good reservoir conditions for the development of coalbed methane. The high rank and difference of coal make different components of coal. The high gas content provides good gas source for the development of coal-bed methane. The negative pressure of coal reservoir, getting the coalbed methane positive adsorption pressure, driving weak motion of the coalbed methane output and having low gas saturation, is not conducive to keep coal bed methane wells high and stable production;The porosity of coal is not so bad but it’s connectivity is poor. The highly-developed transition hole provides a favorable space for coalbed methane storage. Ahthough the small - micro fractures are highly developed but fully filled with coal fines, the permeability of coal seam is low;The adsorption time is longer than usual coal seam, which is unfavorable to the high yield of coalbed gas wells and the short development cycle of coal bed methane.

The coal petrography analysis，proximate analysis and isothermal adsorption experiment of samples from Southwest typical mining area are carried out to investigate the influence of coal quality, metamorphic grade, deformation degree, experimental temperature and pressure on gas adsorption and desorption capacity. The results show that:(1) There is a positive correlation between metamorphic grade and gas adsorption capacity at medium-rank metamorphism stage，and there is a negative correlation between metamorphic grade and gas adsorption capacity at high-rank metamorphism stage, and has the strongest adsorption capacity at the nearby 3 percent of Ro,max (2) The capacity of the coal adsorption has a normal correlation to the vitrinite content and an inverse correlation to the inertinite content of the coal. (3) The capacity of the coal adsorption has a normal correlation to the fixed carbon content, and Moisture and volatile matter in coal can decrease the adsorption capacity of the coal reservoir．(4) The higher the deformation degree, and the stronger gas adsorption and desorption capacity of the coal. (5) the adsorption capacity of gas decreases and the desorption efficiency increase with temperature increase. the adsorption capacity of gas increase and the desorption efficiency decreases with pressure increase.

In order to study the pore structure characteristics of different macro coal components, two different metamorphic stage coal rock samples of low-rank coal and high-rank coal were adopted in the favorable area for coalbed methane exploration and development. Artificial coal and middle coal were separated from coal rock. The pore structure characteristics of two kinds of coal macroscopic coal components were tested using helium porosity, liquid nitrogen adsorption, and scanning electron microscopy experiments. The results of the study indicate that the porosity of high rank coal gangue is higher than that of low rank coal, and the thorium porosity of mirror coal is higher than that of dark coal. The specific surface area of each coal rock component of high rank coal is significantly larger than that of low rank coal, and the specific surface area of dark coal is significantly larger than the specific surface area of mirror coal. The micropores of high metamorphic coal are more developed than macroscopic coal components, and the same metamorphic degree coal , micropores of dark coal components are more developed than the mirror coal components. The porosity, pore structure, and pore morphology of coal are controlled by coalification.

A large number of experiments and data indicate that there are three kinds of flow regimes of Darcy and non-Darcy seepage and diffusion in the exploitation of coalbed methane. Through the investigation of relevant domestic and foreign literatures, the research progresses on the theory of coalbed methane Darcy and non-Darcy and diffusion theory are reviewed, which include Darcy's seepage theory, non-Darcy's seepage theory, linear diffusion theory, infiltration and diffusion theory, nonlinear diffusion theory considering various factors, and analysis of the authenticity and existing problems of these theories, pointing out the development direction in the future.

Abstract: According to the problem that the surface subsidence cannot be controlled in a mine in Jining by the full mining and backfilling mode of solid backfill mining. The necessity of solid backfilling strip mining is analyzed, The yield zone width of coal pillar under the action of backfill is deduced. The design method of width considering the stability of coal column is presented. The mathematical expressions of recovery rate and surface deformation are derived. The variation law of the stress concentration coefficient of coal pillar is studied, which provides support for the parameter selection of the mechanical model by adopting the research method. Combining the results of theoretical analysis and numerical simulation, the width of mining and coal pillar of solid backfilling strip mining are optimized. Results showed that when the mining width is 53 m and the width of the coal pillar is 25 m, surface deformation is controled, ensuring stability of coal pillar and improving resource recovery rate.

Extra large mine main shaft lifting system engineering design supporting technology successfully applied to the main shaft of HongQingHe lifting system project, And in 5 × 6 built-tower 9000kW hoist, AC - DC - AC frequency control system, capacity 50t oversized skip, the fastest lifting speed of 15.18m / s, high-speed stable tank technology, skip replacement technology, High capacity of wellbore equipment, 9.5m diameter borehole wall thinning theory and other technical aspects of pioneering, Completion of the main shaft of Hongqinghe mine hoisting capacity of 15 million t / a huge goal, a major leap in the history of the construction of coal mines, to solve the core constraints confined to large-scale shaft project construction, laying a solid foundation for further technological development, for China has accumulated experience in the design and construction of similar mines and provided new ideas for the mining of extra-large mines.

In this paper, ultrafiltration, nanofiltration, reverse osmosis and electrodialysis were studied, and the characteristics of different membrane separation techniques were analyzed. The application points of membrane separation technology in water desalination, reduction, material concentration and salt separation of high-salt mine water were summarized, and the advantages and disadvantages of different membrane combination technologies were compared. The application examples and operating costs of membrane separation technology in several typical high-salt mine water treatment projects were introduced. The importance and development prospects of membrane separation technology in such engineering applications were pointed out, and providing experience and reference for the design of subsequent similar projects.

In order to eliminate the data silos of various monitoring systems and management systems in coal mines, based on big data and cloud computing technology, this paper puts forward the design conception of coal mine Safety Intelligent control information platform based on cloud platform, designs the platform architecture from perceptual layer, platform layer and application layer, and constructs the basic information management, data networking management, risk analysis index model management, risk analysis and disposal, risk analysis data show five modules. At the same time, according to the established coal mine safety risk analysis index system, through the combination of hierarchical analysis and membership function, the paper realizes the safety risk of coal mine. The results show that the platform improves the efficiency of coal mine data storage, transmission and processing, realizes the effective analysis of the existing data in coal mine, and has a good effect on realizing the safety control of coal mine and improving the essential safety of coal mine.

Reserve management of large coal enterprises has the characteristics of rapid change in the number of resources, large geographical span and multi-level management, so it is difficult to manage by traditional technology. Based on the characteristics of reserve management business requirements of coal enterprises and the application of GIS technology, this paper puts forward a solution of "managing mine by drawing, managing reserve by drawing", develops a reserve graphics management system, realizes the combination of reserve graphics and attributes, satisfies the management requirements of large coal enterprises at all levels, and dynamically reflects the Mining and utilization of coal resources in real time. The reserve graphics management system has been used in Shenhua Group and all its coal mines, strengthening the supervision of the enterprise, effectively promoting the recovery of resources.

In order to solve the problem of optimization of dumping plan for an open pit mine, the AHP method and the GRAP method are organically combined to establish a comprehensive evaluation model of AHP-GRAP, and the comprehensive evaluation of the alternative soil dumping scheme is preferred.Taking the production stripping ratio, coal mining distance, stripping distance, stripping lifting height, and dumping space of internal dumping site as the evaluation index, the corresponding engineering quantity is calculated by three-dimensional modeling and simulated mining technology to determine the parameter values of each index.The weight of each evaluation index is objectively determined by the analytic hierarchy process, and then the model vector to be tested consisting of the importance of the evaluation indicators in the criterion layer and the preferred feature matrix composed of the relative weights of each factor in the scheme layer are given according to the gray comprehensive evaluation method. Through the correlation calculation, the comprehensive evaluation value of the three schemes based on the evaluation index is determined.The results show that the third northern advancement scheme is optimal.

This paper briefly introduces the latest laws and regulations related to coal industry hvac, under the new policy and the situation is analyzed, the coal industry development direction hvac design. In accordance with the new heat source of heat transformation and faced to the mine design problem, respectively discusses the gas boiler heating plan and thermal storage, coal-fired boiler heating boiler heating solutions, solar heating, air compressor heat heating scheme and waste heat utilization in mine spent heating heat source scheme and design principle. Analyzed the six heat source heating operation cost, analyzes the advantages and disadvantages of various options. Results show that the solar energy and waste heat of air compressor in mining area is insufficient, the lowest cost of coal-fired boiler running relatively most provinces, but the cost is the highest, gas boiler cost is the lowest, but the highest operating cost. Comprehensive analysis shows that waste heat utilization in mine should be the preferred spent scheme as a heat source alternative mining area.

Based on the fully analysis of regional geological and hydrological conditions of the East return air shaft in Yuanzigou Coal Mine, The related technical parameters of freezing method construction are determined, and the shaft lining structure is designed. The relevant auxiliary measures of freezing method construction are described to ensure the safe and rapid construction of the shaft, and it can provide strong technical support and scientific guarantee for the coalmine which in similar conditions.

In this paper, based on the practical problems of field engineering, the regional outburst prevention technology and application research are carried out for the deep high gas coal seam roadway uncovering problem. Firstly, boreholes are drilled in front of the roadway to detect the occurrence of coal and rock mass in front of the roadway. Secondly, the outburst danger of coal body is predicted by monitoring gas pressure, gas content and coal strength. The coal body in front of the roadway is determined to be outburst coal body. The regional outburst prevention technology of combined surface-underground coal washing is put forward, which is used for track roadway and return air, respectively. The outburst elimination of roadway was carried out, and the effect of regional outburst elimination was tested. Finally, the roadway coal uncovering was successfully implemented. In this paper, the combined surface and underground coal washing regional outburst prevention technology effectively prevents the occurrence of coal and gas outburst, provides a research basis for similar engineering problems, and has high social benefits and application value.

For the roadway driven along next gob and heading adjacent advancing coal face in close distance coal seams, the excavation process is subject to the multi-perturbation of the coal pillar left by the upper coal seam, the leading support pressure of the upper section working face, the hysteresis support pressure and the lateral support pressure of the goaf. The resulting maintenance problems are analyzed by theoretical analysis and numerical calculation methods, and corresponding support schemes are developed. Through the underground industrial test and the whole process of mine pressure monitoring, the rationality of support scheme is verified, the specific range of disturbances at each stage and the plastic damage range of coal pillars are determined. Thereby providing a basis for the next working face roadway layout.

Based on the backdrop of filling retaining roadway with super-high water material in the coalmine in Shanxi Province, a synergistic control technology of cable-stayed anchor cable-filling body-U steel is proposed combining with the characteristics of surrounding rock movement of in-situ retained roadway. The key of this technology is to make full use of the suspension effect of stayed anchor cable on roof rock stratum, and to form a stable cantilever beam structure with solid coal side as the fulcrum of overburden rock with the cutting of U steel and single pillar. Besides, the super-high water filling body with certain compressibility yields moderately at the initial stage, adapts to roof deformation, and bears load at the later stage, which limits the lower strata to break and keeps the roadway stable for a long time. In the initial stage of field application, the observation of rock pressure shows that the retained roadway has obvious lagging deformation characteristics, and the roof is stable. The main deformation of the retained roadway is floor heave, which is the key point of surrounding rock control of the retained roadway. Combining with the observation results, the reasons are analyzed and the supporting scheme is adjusted. By measures of dense pillar roof cutting, pre-support and bottom bolting, the deformation of roadway is obviously reduced, and the requirement of secondary mining can be satisfied without repairing or simply undercover.

Abstract: In order to solve the problem of bottom plate deformation in deep soft rock roadway, Chen Silou coal mine proposed a grouting + anchor + anchor cable reinforcement technology. In this paper, combined with the reinforcement construction process of the pump room and the substation floor in the No. 9 mining area of the Chensilou coal mine, the bottom drum deformation mechanism, the principle of joint reinforcement, and the construction method were analyzed and introduced in detail. The observation results indicate that the floor drum phenomenon in the pumping room and substation of the No. 9 mining area has been well controlled, providing a technical reference for future similar projects.

Aiming at the characteristics of ground pressure distribution in large dip angle subduction pseudo-inclined working face, combined with the mining geology and engineering conditions of large dip angle close-range coal seam group in Huainan Coal Mine, this paper studies the evolution characteristics of abutment pressure in different mining stages of large dip angle subduction pseudo-inclined working face. Based on the field observation data and numerical simulation analysis, the abutment pressure distribution and numerical calculation model in front of coal rib in large dip angle coal seam with subduction and pseudo-inclination mining at different mining stages are constructed. The action range of abutment pressure in front of coal rib is calculated, and the saddle-shaped distribution of abutment pressure in subduction and pseudo-inclined working face in large dip angle coal seam is revealed. Through theoretical analysis and field measurement, the periodic weighting step and roof weighting strength of working face are analyzed, proposing the ground pressure control measures of working face and achieving good economic and technical benefits.

ultrashort hydraulic slit is an effective method to improve the permeability of coal seam. In response to the problem of gas control in Xintian coal mine in Guizhou mining area, low drilling concentration and fast flow attenuation, long coal seam gas management time and difficulty in management, can not effectively solve the problem of efficient gas extraction, which directly causes low gas extraction rate in the mine. "Pumping, mining, digging" ratio is out of balance. In order to improve the gas extraction effect of the M9 coal seam in Xintian Coal Mine, solve the difficult problem of low gas permeability and low coal seam extraction efficiency and poor stress relief effect, shorten the gas treatment time, improve the permeability of coal seams, and reduce the amount of drilling. The use of deep drilling and high-pressure hydraulic cutting technology to increase penetration in the 1901 working surface has accelerated the pumping efficiency of the 1901 excavation working surface, reduced the extraction time, and achieved the "safety, science, accuracy, economy, and efficiency" of the 1901 excavation working surface. Gas disaster prevention and control, To achieve safe and efficient production and sustainable and healthy development of coal mines.

In order to solve the problem of extremely uneven gas pre-drainage time in various areas of high gas long distance mining face. Based on investigation of drainage radius, the optimum design plan for gas pre-drainage boreholes in coal mining face was put forward. The effective drainage radius of gas pre-drainage boreholes in coal mining face was investigated by gas reserve method. The effective drainage radius of gas pre-drainage borehole for different pre-drainage time in coal mining face was obtained. The high gas long advancing distance mining face was divided into several blocks according to the length of gas pre-drainage time. Each block of gas pre-drainage borehole was designed according to its effective drainage radius. The longer the pre-drainage time was, the larger the distance between the pre-drainage boreholes. The shorter the pre-drainage time was, the smaller the distance between the pre-drainage boreholes. Achieve the standard of gas drainage at the coal face mining and minimize drilling works at the same time. The results of field application showed that, the optimized design of gas pre-drainage borehole was adopted in the 2311 mining face, the amount of drilling engineering was reduced by about 70 thousand M, and the gas pre-drainage time of coal face mining was about 15d, and during the mining period, gas drainage standard and safe mining were achieved. The optimal design of gas pre-drainage borehole in the mining face based on investigation of drainage radius was adopted in the high gas long advancing distance mining face, and good technical and economic benefits had been obtained.

Abstract: In order to reduce the low gas coal mine gas “U” type ventilation in upper corner gas concentration, improve the extraction efficiency of the coal mining face in Fenghuang-shan mine 15# coal seam XV1306, high drilling working face as the research object, theoretical calculation of influence of key technological parameters of drilling drainage, respectively from the effective length and high drilling the utilization rate of drilling parameters, the two aspects of reasonable spacing and the number of boreholes are calculated and simulated numerically using COMSOL software extraction time and extraction effect of negative pressure recovery effect of high drilling of high drilling parameters were optimized. The practice shows that XV1306 high gas coalface high drilling and drilling field after optimization, production efficiency and improved pumping type “U” gas ventilation of coal face, the upper corner gas concentration decreased, the effect of gas field significantly, thus ensuring the safe and efficient mining.

In order to ensure the safety of the mine downhill roadway, prevention and control of the mountain induced rock bursts, the creep deformation of roadway in insisting on the principle of saving effective utilization of resources, to study the creep deformation mechanism of the gateways, explores the stress system online analysis scope of abutment pressure and combined with the micro seismic monitoring rock rupture range to determine the reasonable mining line method. Based on the stress monitoring data and micro seismic data of 109 working surface of Shandong Tengdong coal mine, the reasonable stop-pick line position was determined.

The comprehensive mechanized coal mining equipments cannot be used normally due to problems such as failure, wear and aging after a certain period of time and a series of equipment maintenance should be needed. Due to many factors such as the complicated structure of the equipment, different operating conditions, various specifications and sub - series, and different abilities of maintenance workers in various mines, the equipment maintenance quota system is extremely difficult, and the project cost is extremely inconvenient to implement. Therefore, on the premise that our country is still in the blank field at present, we have carried out the work of compiling the maintenance quota of comprehensive mechanized coal mining equipments without reference. In this thesis, we have studied the process of compiling the maintenance quota of comprehensive mechanized coal mining equipments deeply, and put forward a set of feasible methods for compiling the quota. At the same time, we expound the problems and difficulties encountered in the process of compiling the quota and the corresponding solutions, and hopes to give some supports to the perfection and perfection of the maintenance quota of comprehensive mechanized coal mining equipments.

Based on the characteristics that temperature and pressure affect the adsorption of methane on coal, the adsorption of methane on coal at different temperatures and pressures and the deformation of coal during adsorption are studied. The results show that: the adsorption of methane to coal decreased with increasing temperature. High temperature inhibited the adsorption capacity of coal; The axial deformation of the standard coal sample after adsorption of methane is negatively correlated with temperature and positively correlated with pore pressure. At the same temperature, with the increase of pore pressure, the adsorption amount of methane in the coal body increases almost linearly; when the temperature is 80 °C, the coal body undergoes significant compression deformation.

To improve the efficiency of the main parameters of the shearer and the synergistic efficiency of the fully mechanized mining, the technical parameters of the shearer and the synergy process between the three fully mechanized mining machines are used to learn the technical parameters of the shearer, propose a biological model of shearer. The tec hnical parameters of the shearer are studied, the potential relationship between the parameters is determined, and the synergistic relationship between the shearer and the hydraulic support and the scraper conveyor is established. Based on the extreme learning machine, the technical parameters prediction model of the shearer is established. The experiments show that the accuracy of the model is above 95%, which meets the application requirements. The prediction model is used to solve the technical parameters of shearer and the matching parameters of conveyor and hydraulic support, which improves the design efficiency and quality.

In order to study the positioning error of the roadheader, based on the ultra-wideband ranging technique, according to the Time Sum of Arrival(TSOA) positioning principle, indirect method was used to solve the coordinates of the positioning point. The distribution of positioning points in space was simulated and analyzed. The positioning errors of the three coordinate axes were analyzed, and the distribution law of positioning errors in the range of 10m to 100m was obtained, which provided the basis for position and pose detection of the roadheader.

Abstract: the article to SSC1150 sizing crusher deceleration pause as the background, in view of the finite element analysis software for complex geometry structure, cannot be comprehensive and accurate to the disadvantages of its load of modeling, through one-way combination of discrete element and finite element method, based on maximum stress index, on the strength of the tooth roll under different nominal transmission ratio is analyzed and compared. The results show that under the same strength load, the position and value of the maximum stress on the tooth roller are different when the nominal transmission ratio is different. At the same time, it can be seen from the cloud chart of maximum stress suffered by the toothed roller that the maximum stress value suffered by the toothed roller can be effectively reduced if the nominal transmission ratio of SSC1150 sizing crusher is 20 in the selection.

Aiming at the power unbalance problem of the head and tail motors during actual working conditions of scraper conveyor, power coordinated control system of scraper conveyor based on CANopen protocol was studied and designed. The system’s whole scheme design was introduced, coordinated control strategy was analyzed, and its hardware structure and software design were elaborated. The test results of experimental platform showed that, based on CANopen communication and rotary speed of motors regulated with real-time load change, the system can realize power coordinated control of two motors under the condition of load fluctuation effectively. It provides a new idea for study on power control of drive motors of scraper conveyor.

Based on the analysis of the application area and function of coalbed methane truck-mounted drilling rig, a remote electro-hydraulic control system is developed to improve the automation level of drilling rig and reduce the hidden danger of personnel safety. The system is mainly composed of electro-hydraulic double-control hydraulic valve, camera and remote console. CAN bus communication is used to quickly connect with the electric control system of drilling rig. The control demand and signal type of drilling rig are introduced with the controller as the core in the remote console. The writing method of analog input of handle and PWM signal output of proportional valve in the software design of CoDeSys is described in detail. Construction application shows that the system can realize remote electronic control operation of drilling rig. The response time of proportional valve is less than 0.8s. It has high reliability and portability. At the same time, it simplifies the arrangement of long-distance pipeline, makes drillers far away from wellhead, reduces labor intensity and improves construction safety.

Most coal mine extraction design software uses AutoCad, which has low efficiency and large workload. The graphic design attributes can not reflect the design ideas well and clearly express the correlation between extraction engineering and rock formation. Aiming at this problem, the design method and model including the bedding layer and the layering drilling hole are studied. The GIS platform is used to design and develop the general drilling intelligent design software to realize the computer intelligent design of the drilling and drilling under various requirements. The application in the Xinjian mine shows that the system can carry out the bedding or through-hole drilling design conveniently and quickly. Under the premise of satisfying the no-drain blind zone and reaching the control range, the drilling quantity is minimized, which effectively improves the drilling of the design department.

In order to grasp the performance deterioration law of coal gangue under the harsh erosion environment such as sulfate, this paper did indoor simulation experiment and selected four kinds of coal gangues from Tai Yuan, Chang Zhi, Yu Lin, Xu Chang as research target. Strength deterioration of coal gangue and evolution of coal gangue-cement ITZ structure under dry-wet cycle in sulfate/water were studied by macro and micro testing. The results show that water and sulfate solution have significant erosion effect on coal gangue. Under the conditions of water immersion and dry-wet, the softening coefficient of the four coal gangues is only between 0.3 and 0.4, which is significantly lower than that of limestones. And under dry-wet cycle in sulfate solution, their strength reduction rate can reach 80%. The dry-wet conditions of water and sulfate solution also have significant deteriorating effects on the interfacial transition zone（ITZ） of coal gangue-cement. These research results can support the application of coal gangue in roadbed fillers and concrete.

In view of the problems of low speed, low efficiency, high risk coefficient and more personnel participation in the existing mine tunnel, a kind of drill-anchor robot was proposed, and its layout net unit was designed. modeling it in three dimensions software base on SolidWorks, the key components were analyzed and the finite element analysis was carried out in ANSYS software, and the simplified sample model of the layout net unit of the drill-anchor robot was set up in ADAMS software, and drill-anchor robot of layout net unit was simulated and analyzed including catching the net, lifting the net. The results show that The overall structure design of the drill-anchor robot’s layout net unit was reasonable, and it satisfies the requirements of stable catching, moving and lifting posture of the supporting net, and the key components of layout net unit manipulator meet the requirements of rigidity and strength.

To allocate limited management resources reasonably to ensure the safe production of coal mine, a practical survey of Wan Feng coal mine was conducted to classify the hazards from three perspectives: the type of risk associated with the hazard, the possible types of accidents, and the risk level. The method of task analysis and risk matrix method was used to make the risk identification and evaluation, forming two main lines of safety production risk analysis and control, further carrying out the comparative analysis of the first line through the analytic hierarchy process of expert angle and the hundred points weight method of frontline worker. The results showed that the two main lines of human unsafe behavior at higher risk levels in high frequency risk type and types of accidents with high frequency occurrences in high-risk grades could take specific point-to-point control measures against hazard sources and types of accidents. The cooperation between the two can control the overall safety risk of mine, determine the important contradictions in the safety management of the mine, avoid the blindness of coal mine safety risk management.

Abstract: To change the present situation that the project cost management is only limited to the construction stage or even the project budget and settlement work, the project cost management should be carried out throughout the whole project management process, such as project decision-making, project design, construction supervision, completion settlement, project audit, etc., and the whole process of control and management should be fully developed. It is a necessary measure to control project cost effectively and an effective way to improve project management level to exert its management functions such as evaluation and control. In the whole control process, project decision-making and design is the decisive stage. It has become a common consensus of construction units to move the project cost management to the project decision-making and design stage. This paper focuses on how to strengthen the cost management of project decision and engineering design stage.