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Deep mining operations require special measures in order to keep safe and economic aspects. After mine ore is extracted, voids are created and need to be filled with high-strength, low-cost materials. Cemented Paste Backfill (CPB) has recently become one of the main alternatives in filling stopes. Although numerous papers have mentioned the magnitudes of the strength of this material, its behavior under high confining pressures is still not well understood. Therefore, the purpose of this study is to increase the knowledge regarding the CPB behavior. Triaxial compression tests were performed using a Hoek Cell and Load Frame System under high confining pressures. Samples with two different binder contents were used in order to obtain the CPB strength improvement. Besides the self-weight consolidation curing method, samples were subjected to a different curing method that simulated a zero gravity condition (rotating wheel) in the first curing day to compare their mixture properties. The results suggested that both curing method and binder content have influenced the geomechanical properties of Cemented Paste Backfill. By increasing the curing time, the CPB shear strength has increased slightly, whereas specimens with higher binder content presented a significant increase in shear strength values.

With the increase of mining depth, rock mechanics conditions become complicates. So the surface subsidence law caused by deep mining is different from the shallow. Based on the finite difference method and rock mechanics theory, the surface subsidence law cased by deep caving mining was studied, the strata movement rule and characteristics of stress distribution of different excavation stage was analyzed systematically. The results of the study can provide certain reference significance for the deep mining to confirm the displacement angle and range of surface subsidence.

Traditional trellis support was mainly used in deep mining roadway of Kailuan group. With the increase of mining depth, section of roadway and deformation of surrounding rock also increased gradually. As a passive support ways of roadway, trellis support had been unable to meet the requirements of high yield and high efficiency comprehensive mechanized mining. Therefore, anchor bolt supportis in urgent need to turn passive support into active support and to ensure the safety and the stability of surrounding rock of roadway, meanwhile, the cost saving and boosting yield was made sure. This paper is based on the physical and mechanical parameters of coal seam roof and floor of working face 1357w, numerical simulation method was took, and the parameters of anchor bolt support suitable for the roadway with working face were also studied. The result of study could provide theoretical basis for later projects.

There are many problems such as depth, high in-situ stress, high ground temperature and rockburst proneness etc. in deep mining. And it is an acknowledged and urgent mining technical puzzle about mining method of gently inclined and medium-thick ore bodies. For such an ore body in West wing of Dongguashan copper mine, if we use traditional mining method, it is hard to conquer such difficulties as high in-situ stress, large open area in roof, removal of mined ore by gravity etc. The theory of “large panel and lower sublevel height” will be easy to solve such problems. This paper use numerical technology to analyze and compare the technical and economical effectiveness for different selected mining method and its structure. The sublevel (at a height of 12 m) open stoping with back-filling by extraction in two steps is quite suitable for ensuring safety, increasing efficiency, productivity and reclaiming resource. The selected method is feasible and well worth spread.

This paper takes typical stoping of deep-mine dynamic pressure working face of Zhaogezhuang mine of Kailuan mining area for the research background, relieving the dynamic pressure of roadway of burst tendency through building defect method in dynamic pressure roadway. Putting forward the theoretical solution of defect method in dynamic pressure roadway based on elastic-plastic theory;Taking numerical simulation method in view of the material inhomogeneity of actual engineering geological, researching the characteristics of stress distribution of roadway surrounding rock after relieving in defect method; Applying the theory to the stoping of deep-mined impact working face, and the implement effect is good on the spot.

The instability failure of coal and rock mass occur frequently in deep mining. However, this destruction occurs with abnormal intensity and suddenness, with hardly any obvious macro precursors. The ability to extract this precursory information and make certain the relationship among the parameters is therefore important. During the process of instability and failure of coal samples, the evolution characteristics of deformation field were monitored by digital image correlation system. Base on the researches, the appearance of the deformation localization band could be divided into three time periods for the samples which all had splitting failure. During period I, the relative sliding component increased rapidly. During period II, the relative tension component increased rapidly. During period III, both the relative tension and relative sliding components increased rapidly.

In order to understand bursting liability and related mechanical properties of roof mudstone in east mine of Kouzi, SANS material mechanics testing machine is utilized as power equipment, bursting liability and related mechanical properties of roof mudstone has been tested, and MATLAB is exploited to analyze mathematical analysis for results. Experimental results showed that roof rock with strong bursting liability in east mine of Kouzi, its relevant safety should be improved; we can adopt the way of water injection into roof strata to change its mechanical properties, the purpose of safe mining is achieved. Research conclusion provides theoretical basis for safety mining in deep Yongchuan mine in east of Kouzi.

Traditional subsidence range prediction by stagger angle doesn’t adapt to production situation in deep mining, the angle is usually large. Analyze the lateral support force of the moving bulk solid in the subsidence pit based on maintaining sidewall rock stability of subsidence pit. While bulk solid thickness of subsidence pit is not less than critical bulk solid column, the active pressure and passive pressure of bulk solid prevent the scaling of sidewall rock together. By analyzing the measured data of subsidence range of Xishimen mine, the height of critic bulk solid column relates to stability of rock, sidewall angle of goaf, internal friction angle, and rock loose coefficient. In deep mining, that filling subsidence pit with waste rock can lower the critical depth and control surface subsidence range.

Among the main geological factors to cause the disasters of mine safety production in deep mining, coal and gas outburst is the first major calamity that restricts colliery exploiting. Aiming at this problem, current geophysical methods were reviewed and compared, and the velocity tomography technology using ground penetrating radar was studied. Two models with ground stress anomaly and collapse columns were built and inverted using LSQR algorithm, respectively. The results show that the proposed method gives very consistent results with respect to the models information, and uncertain features of inverted models were identified accurately. This verified radar velocity tomography is effective and practical.

For occurring frequent thin seam rock burst disasters in deep mining stage in Xinxing Mine, through summarizing the mineral basic geological and mining conditions, on this basis, analysing the occurrence characteristics of rock burst with statistical method in Xinxing Mine, analyzing the inducing factors of thin seam rock burst, and through FLAC3D roadways along on 41,051 workface exploitation right beside left stacks of rock burst was simulated, and made a rock burst prevention focus for the impact of land pressure control system provides an effective basis. On thin hard coal burst prevention of important guiding significance.

With the development of deep coal resources, rockburst, as a kind of typical underground dynamic disaster, always threats the production safety. Before the mining design, it is very necessary to forecast the possibility of the rockburst. This paper takes the Guo-tun coal mine for the object, considering the specific geological conditions, to predict the possible dangerous area where rockburst would happen. Through the comprehensive research and analysis, the paper would divide the 1312 working face into some probalble dangerous zones, namely strong shock hazard zones and medium dangerous impact zones, during gateway driving and stopping.

To prevent threaten of impact disaster, high-pressure water is injected into coal face, which is most widely used in impact-type mine. In such cases, by analyzing the rock burst tendency of a particular type of deep mining pit and occurrence of the mining process, rock samples drilled from the coal mine were taken for the conventional mechanical properties test and rock burst tendency test respectively under dry and wet state. Cuttings volume indicator affected by injection has been optimized to improve the prediction sensitivity. "One shift anti-impact, two-shift production "patterns labor organization model, adjusted development system layout and cut drilling index optimizations, as well as the allocation of high-pressure water injection drilling means, greatly improving the water injection effect, which probably provide a reference for similar mines to safe and efficiently mining.

In order to study the high temperature heat harm problem in the process of deep mining, Briefly analyzed the causes of high temperature by using the methods of theoretical analysis and field measurement. In addition, a series of high temperature control methods are put forward. Including take conventional non-artificial cooling and the artificial refrigeration cooling methods as well as new cooling methods of using geothermal energy cooling and combined cooling heating and power technology so many initiatives to solve the problems of high temperature of deep mine. The engineering practice proves the reliability of mine cooling technology,the results can provide a basis for prediction and control of high temperature of deep mine.

The impact disasters of rock burst and pressure bump are common problems of underground construction and deep mining [1-. This paper selected the typical mine based on the work of field crustal stress measurement, indoor rock mechanical experiment, parameter calculation, numerical analysis and field disaster investigation, etc,. Deeply analysed the basic types and potential laws of possible impact disaster after a mines main tunnel excavation based on the study idea of experimental rock mechanics and computational rock mechanics co-ordination and additional verification.

In the process of deep mining, mining roadway has severe deformation and high deformation speed. Arranging mining roadway is an effective way to reduce deep roadway deformation under the mined-out area. This paper uses FLAC3D Fast Lagrangian Analysis of Continua to make the coal rock geological structure modeling, works out the stress and strain state of coal and rock in different ways when arrange mining roadway under goaf, and then get the influence rule by comparing and analyzing the computed result, providing reliable and efficient theoretical foundation for arranging mining roadway under goaf.

The geological structure is an important factor of gas occurrence in coal seam, and the gas occurrence in deep coal seam should be paid attention to enough because the occurrence was more controlled by geological structure and influence. Taken Fengfeng coalfield as target in this paper, the geological structure of this coalfield was described. The deep coal mining district which is monoclinic structure in Fengfeng is located in the east of Gushan anticlinoria, which the junior small anticlines and synclines of the sub-echelon are well developed. And regional fault structures are intensive, the pressure structure is the major structure among this region. The characteristics of geological structure in Fengfeng coalfield were analyzed. The tensional structure planes and pressure structure are the major effect factors, and the latter is the main form of gas occurrence in deep. Some suggestions on safe of deep mining in high gas environment is also put forward, in order to provide theoretical support for the deep coal mining and gas disaster prevention.

In order to study the mechanics of the deformation of the wall rock, the right roadway in Chengshan mining field, Jixi Mine was chosen to determine the physical property, micro-structure, ingredients, clay and the inner-relationships between these properties using scanning electron microscope (SEM) and theoretical analysis. For further understanding the deformation mechanics within the wall rock, hollow inclusion stress release method was used. At the end, mechanism of the wall rock in the deep was established and corresponding deformation control technology was discussed by numerical simulation.

Large strip mining technology could effectively control the surface subsidence inducing from overlying strata movement and realize green mining. Bored stress and deformation sensors were laid in 4301 working face pillar of Shandong energy zibo mining group tangkou coal, analyzing the strip pillar stress pre and post working face; numerical simulation was used to study the influence of overlying strata from reserved size of strip pillar. According to the observation results of surface movement and deformation, law of surface movement and deformation characteristics was studied, which contributed to the practical application of large strip mining technology under deep mining and had the important theoretical and practical significance for mining under buildings ,railways and water in Chinese.

Some damage phenomena often happens in deep mining, in order to study and solve that difficult problem, three finite models are established. The shear stress, minimum principle stress, and maximum principle stress and displacement distribution is analyzed. Some useful results are got, and it has some reference value to tunnel mining engineering.

Some engineering damage often appears in deep mining. In order to solve that engineering problems, finite element software ANSYS is used to analyze roadway displacement and stress under different support conditions, which including model with on support, with anchor support, with anchor and cable support and with U steel support. Some useful results, which have reference value to mine engineering, are achieved in this study.

Mine into the deep mining, the power disaster occurs mechanism more complex features fuzzy disasters and hazards common. Outburst and rock burst and other disasters are common differences, the use of traditional coal seam outburst hazard identification method has limitations. According to the kilometers deep test area, the individual indicators law 13-1 coal seam the outburst hazard identification,13-1 coal seam first mining area were identified as non-prominent seam. While outburst identification test area seam burst tendency identification,13-1 coal seam has a strong burst tendentious. The test mine disaster prevention should also consider bumping prevention and control not only consider the gas control. Project research results have important reference conditions similar to mine.

On the basis of the important role of the overlying strata movement in safety prediction and control of coal mining, indoor similar material model test was conducted to study on the movement characteristics and the destruction regularities of the overlying strata from the deeply buried sublevel caving coal mining. The generation position and its extension regularities of overburden bed separation after the mining were analyzed. In addition, the impact of abutment pressure on movement conditions and structure damage of strata combination was explored. Lastly, characteristics of the rock beam subsidence and surface subsidence were discussed with the intention of providing basis for the design of pressure control of stratum movement and mines.

To solve this difficult technological problem that predicts the surface subsidence that induced by deep mining of large steep deposit. Through understanding engineering geological characteristics and mining conditions for a certain mining area, the three-dimensional simulation model of deep mining with a high degree similarity in space and mechanics morphology have been established, and the exploitation of the mining area has been systematically simulated. After excavation of the third stage, the calculated values of surface subsidence coincided with the measured values of GPS. Then it has been more accurately predicted surface subsidence and displacement angle and the range of surface deformation which were induced by deep mining in fourth stage project. It provides the basis for the positioning of underground engineering and design of the range of ground movement in deep mining.

With the continuous mining of coal, many mine have entered the deep mining mine ranks. Many problems which caused by the deep mining, especially the mine rockburst has had a significant increase, and a more and more serious trend, this has seriously affected the safety production[1]. There are many rockburst factors, and by the mining process and mining, its leading factor was difficult to be determined during mining. However, analyzing the mining process, and researching the influences of mining process on rockburst, making effective means of monitoring, adjusting the recovery process parameters, there are practical significance on mine safety. Reserving stacks along the gob tunnel is a mining technique which many mining often used. The document conducted numerical analysis towards the vertical stress distribution in the stacks, and come to a conclusion about the mining technique influence to shock bump, which has provided the basis for the recovery process parameter adjustment. Practice has proved that the method is feasible. The results of the analysis have practical significance.

Alternate Room-Pillar Mining Method with Ascending Backfill is now used in deep mining of Sanshandao Gold Mine. In mining practice of the metal mines, the widths of the room and pillar vary from 6m to 15m. In order to improve the production capacity and solve the deep mining safety problems, a fuzzy optimization model containing 11 evaluation indexes was built to choose the optimal structural parameters among 8m×8m, 8m×10m, 10m×10m, 10m×12m and 12m×12m. The fuzzy comprehensive evaluation results prove that the optimal stope structural parameter is 10m×10m for safety and high efficiency mine operation.

According to the 8000t/d production capacity planning and high in-situ stress, high rockburst proneness in deep mining of Sanshandao Gold Mine, three mining methods were compared and analyzed from safety, technical and economic indexes. Fuzzy optimization model was built to select the optimal mining method based on mining indexes quantification and fuzzy analysis of mining indexes. The conclusion shows that Alternate Room-Pillar Mining Method with Ascending Backfill is the optimal mining method to satisfy the safety and high efficiency demand of deep mining in Sanshandao Gold Mine.

With the increasing of exploitation scope and intensity, the deep mining would be the essential choice, where the heat-harm of high temperature becomes one of the main barriers. Through analyzing the thermal damage feature, the cooling technology were be used that put the mine discharge as cold source to control the heat harm. By disposing three main workstation, the technology can be accomplishes its operations and corresponding functions in different exploitation level. Particularly, the exchanged heat source form the workplace is taken to ground heating by the circulating water which being acted as a carrier. It show that the design concept of this technology include protect the environment and reduce the emission of deleterious air. The results of the project illustrate that the technology to control the heat-harm is efficient. The temperature of the workplace is brought down to 26-29 centigrade, and is 4-6 centigrade lower than the original, and the relative humidity is 5-15﹪ lower than before. It is greatly improves the working environment of the workplace where the heat-harm of high temperature and high humidity lasts for a quite long time. In addition， it extracts deep geothermal energy successful replacing ground fired boiler for heating, further reducing environmental pollution.

Rock burst is a common mine dynamic phenomenon in the world, and the research on bursting liability of coal and rock is the foundation of rock burst’s prevention and treatment. This paper has a research on bursting liability of coal and rock of 11-2 coal seam which is the main coal seam of Zhuji coal mine, and through the research and analysis of coal seam burst energy index(bursting energy index, elastic strain energy index, duration of dynamic fracture) and rock seam burst energy index(bending energy index), this paper given that seam and rock in deep mining section of Zhuji coal mine has bursting liability, put forward a series of countermeasures such as the previous water injection, hole-drilling method, blasting distressing to the coal seam with the impact disaster for deep mining in Zhuji coal mine.

The paper takes the deep exploitation of Sanshandao gold mine as the research subject , the methods of distribution of rock structure and lithology examination, in-situ rock stress measurement, physical and mechanical tests of rock, and fuzzy mathematic prediction are used to study rockburst tendency in deep development and exploitation of the mine, which fill the gaps for the past using only one qualitative indexes of rock to judge the possibility of rock bust, and make the evaluation results more close to the objective reality.

In order to further research the expansion of cracks in the rock during hydraulic fracturing, this paper theoretically analyzes the stress state of wall cracks. According to the effective stress criterion of Terzgahi, it gives the mechanical condition of the rock crack expansion. By Moore-coulomb's law, it analyzes the influence of the water pressure in the pores of space wall on the rock fracturing. On this basis, the hydraulic rock fracturing is applied to build physical experiment model of deep mining mine water bursting. By the methodology of combining the analysis of experimental results and theoretical analysis, it analyzes the change of water injection pressure in the hole with rock fracturing and the stress strain relations during rock’s uniform displacement change and loading. The experimental results show that in the process of the water pressure and vertical loading, the increasing fracture load on the rock, constantly produces, expands the cracks and fractures to instability; the mutual influence of water and pressure comes to be the major problem of deep mining rock fracture and mine water bursting.

Because of deep mining and the serious dynamic pressure appearance in Zhaogezhuang coal mine, this paper has statistical and analyzed phenomena of dynamic pressure appearance, and proposed the engineering defects method to relief the pressure for high stress zone of working face and roadway according to the actual situation, which can transfer the stress distribution of coal rock and release impact energy. Based on the numerical simulation analysis of pressure relief on cavity defects, it has analyzed the feasibility of pressure relief using engineering defect, acquired good effect of pressure relief and achieved the safety of coal mining in the 2337E working face.

With the deep mining in coal mine, heat damage is one of the technical issues need to be solved. HEMS cooling system in Sanhejian Coal Mine is a process system for high-temperature heat damage controlling in deep coal mine, in which cool energy extracted to reduce work face’s ambient temperature to achieve heat damage controlling. Part of the cool energy is from the level circulating of cooling water in -700 level main raodway, the other is from the mine water. We analyze the energy consumption of every subsystem during operation of the HEMS system, which could provide a theoretical basis and technical guidance on more efficiently running of cooling system deep in the future.

At present, the mines in our country gradually shift from the shallow mining to the deep mining, but the deep well floor is particularly serious hazard by high pressure underground water.This article considers the high pressure underground water as three-dimensional transient flow, sets up mechanical model by combining mechanical knowledge and to analyze the destructive action on floor from two aspects. On the one hand, researching the impact destruction of high pressure water at different positions of floor ; the other hand, to analyze mechanical function on fracture development from high pressure water.

Heat damage caused by deep mining is the inevitable trend in coal mine development. HEMS cooling system is a process system for high-temperature heat damage controlling in deep coal mine, in which cool energy in mine water extracted to reduce work face’s ambient temperature, to achieve heat damage controlling. We analyze the energy consumption of every subsystem during operation of the HEMS system, which could provide a theoretical basis and technical guidance on more efficiently running of cooling system deep in the future.

The support of surrounding rock under the condition of deep mining has significant challenges due to high stress and low rock strength environment. Using the method of strengthening broken rock, reinforcing support force and releasing the mine-induced stress, this study has pointed out the complementary support technology which is based on the support using bolt-wire-shotcrete and is combined with steel arched yielding support. For the purpose of permanent support, the complementary support technology could combine the each support element and adequately take advantage of load-caring capacity of surrounding rock. The monitoring data of Xiaokang coal mine, Muchengjian coal mine and Yangquhe coal mine indicate that, for the various geological conditions, complementary support system has provided powerful support force to resist large deformation of weak and broken surrounding rock. It is proved that this type of support technology could reduce the mine-induced stress as well and has economical significance.

After ore mined, the equilibrium state of original rock stress around mining area is damaged, causing surface deforming at large range. With the increasing resource needing and mining intensity, the mines all over the world are gradually in a stage of deep mining, so it is important to study the principle of surface deformation under the condition of deep mining. Finite element method is used to simulate mine process with increasing depth, and the relationship between mining depth and surface deformation is achieved. The result has important reference value to practical engineering.

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.

With the increase of mining depth，most coals in China have been deep mining stage. Compared to the shallow roadway, the characteristics of deformation-failure of surrounding rock show significant differences in the deep roadway, and the deep rock features of the surrounding rock are not considered in the traditional classification of roadway. So it is needed that systematical study on the surrounding rock classification for the stability evaluation of the deep roadway to meet the demand of the support design and the construction of the deep roadway in coal mine of China. The paper puts forward classification system of surrounding rock in deep roadway of coal mine according to on-the-spot geological investigation, rock ultrasonic testing, in-situ ground stress testing and comprehensive analysis on the surrounding rock stability of deep roadway in typical ore area.

The stratum movement and surface subsidence is considered as a whole system in the research work. The key of the surface subsidence control lies first in having thorough knowledge of the dynamic changeable of the overlaying strata movement as the face advances so as to establish the corresponding structure mechanics subsidence model in flat seam and deep mining. The common characteristic of stratum movement and the development procedure of crack arch are described in this paper. The structure constituents of subsidence and their influencing factors are also analyzed. Meanwhile, the surface subsidence is determined by the compressing of coal wall and the bending of the overlying strata. Based on the ground observation by the global positioning system, the boundary angle and the motion angle are determined. Furthermore, according to the research law, one can predict and control the surface subsidence damages for the special geologic conditions.