The geotectonic environment of the gold-mercury-antimony ore belt in the South Qinling Dingjiashan-Majiagou is located in the transitional part between the north China platform and the Yangtze platform.The south side of the Zhen-Ban deep fault is favorable for metallogenic conditions，north wing of Jinjiling compound syncline，and it has been a mining area for mercury-antimony since ancient times，combined with the above characteristics，the geotectonic environment of the gold-mercury-antimony ore belt is one of the important mineral resources in China. At present seventy-five gold bodies，more than one hundred mercury and antimony ore body has been found in the gold-mercury-antimony ore belt in the South Qinling Dingjiashan-Majiagou.Up to now it has been reached supersize，so it became one of the few supersize gold and poly-metallic deposit in Qinling area.The mineralized present mainly in NE-trending and NW-trending fault zone，and then it exist in near NW-trending interlayer shear fracture zone.There are Hg-Sb deposits in the mid-east side of the ore zone(Dingjiashan-Majiagou)，and equally further enrichment of gold and antimony in the western(Guloushan-Jinloushan).The metallogenic belt was divided into seven ore sections from east to west，according to the characteristics of the relativety concentrated mineralization.It respectively are Shijiashan，Dingjiashan，Xipoling，Jinlongshan，Yaojian，Qiuling，and Guloushan.The Au-Hg-Sb mineralization is belong to the same metallogenic series，it has horizontal and vertical zoning characteristics in space，by contrast there is a close symbiotic relationship，and at the same time exist in different strate of the belt.The wall rock alteration closely related to minrealization is mainly silicification and carbonation.When pyritization，arsenopyrite and weak silicification occur simultaneously，which indicates gold mineralization enrichment or the existence of gold orebodies.Jasper veins filled in tensional fault zones，and again broken breccia，stibnite and cinnabar mineralization occur，accompanied by strong silicification and calcification.The metallogenic age is the early Late Mesozoic，which is the metallogenic response of the collisional orogeny in the South Qinling Mountains.The Au-Hg-Sb mineral desposit is made up of the effect of basin-mountain transformation under the tectonic system and late tectonic magmatism，it formed during the transition form compressional to extensional tectonic mechanisms.The formation of Hg and Sb was later than that of Au，so the metallogenic age(phase) extists successively and succession relation.The Au-Hg-Sb ore bodies are controlled by tectonic lithology，the SN-trending compressive stress in Indosinian period formed nearly EW-trending tight anticline folds，and the dome structure formed by overlapping the NE-trending wide and gentle anticline folds in Yanshanian period formed the main structural framework in this area.Joints and nearly EW-trending compression fracture zones （shear zones） developed intensively on the axis and wings of the anticline under intense compression are favorable sites for mineralization，which often directly control the spatial distribution of endogenous metal minerals in the area.The NE-trending faults are the main ore-controlling structures in the area.The other NW and SN trending fault structures have poor ore-bearing property.The main ore-bearing structures in Dingjiashan，Jinlongshan and Qiuling ore sections are NE trending fracture zones.The metallogenic condition of the Ding-Ma ore belt is better ，such as Guloushan,Guojiashan and Yangjialing and other areas without systematic exploration，it has great prospecting potential in the depth and flanks of old mercury mines and in deep parts of known ore bodies.
As one of the famous gold-enriched areas in China，a large number of super-large，large and medium-sized gold deposits have been discovered in Jiaodong Peninsula.Some research had been carried out on the formation mechanism，metallogenic epoch，material source，division of regional metallogenic belt and the temporal-spatial relationship between main geological bodies and gold mineralization in Jiaodong Peninsula.But there is still a lack of detailed understanding of the tectonic ore-controlling conditions，distribution regularities and occurrence regularities of gold deposits in this area.In this study，the regional geological characteristics，the geological characteristics of gold deposits and the ore-controlling characteristics of faulted structures and the metallogenic regularity of gold deposits are discussed，which will provide a reasonable explanation for the above-mentioned scientific problems，and hopefully provide a possible guidance for later prospecting.The middle section of Zhaoping Fault is an important gold metallogenic belt in Jiaodong Peninsula.The following typical gold deposits have attracted possible concerns：（1）Xiadian super large gold deposit and Dayingezhuang super large gold deposit；（2）Jiangjiayao，Caojiawa and Jiaogezhuang medium and small gold deposits.Nevertheless，the structural ore-controlling conditions，distribution regularity and ore body occurrence regularity of various gold deposits distributed in the middle part of the fault zone are still the main problems to be solved urgently.Based on the analysis and summary of the geological characteristics，gold deposit geological characteristicsBased on the analysis and summary of the geological characteristics，gold deposit geological characteristics，structural ore-controlling characteristics and gold metallogenic regularity of Xiadian large-scale gold deposit，Dayingezhuang super large scale gold deposit and Jiaogzhuang small-sized gold deposit，the following results and understandings are obtained.Dayingezhuang super large gold deposit is mainly controlled by Zhaoping main fault.Xiadian super large gold deposit is mainly controlled by main ore-controlling faults associated with lower wall，derived low-grade and low-order faults.Xiadian Beiqu orebody is controlled by local tensional micro-fracture zone of rock mass in lower wall of main fault.The Dayingezhuang，Xiadian and Jiaogezhuang gold deposits in the middle section of Zhaoping Fault zone are approximately isometric.The intersection of nearly EW-trending faults and Zhaoping Faults is favorable for mineralization.The bend or intersection of faults is the main ore-hosting part.
Jiaohe area in Jilin Province is located in the southern section of the Lesser Xing’an Range-Zhangguangcai Rang Fe-Pb-Zn-Cu-Mo-W metallogenic belt.In this area，the stratum and structure is well developed，and the magmatic activity is frequent.It has a good metallogenic condition In 2016，the No.1 Gold Geological Party of Chinese Armed Police Force carried out the 1/50 000 regional geological survey in this area.A gold deposit was found near Ailin region by stream sediment survey and anomaly verification.Field mapping coupled with laboratory research was conducted to investigate the mineralization geological characteristics and genesis of Ailin gold deposit in Jiaohe，Jilin Province.Field mapping suggests that the orebody is restricted by the NW faults and the wall rocks are mainly consisting of silty rock，belongs to Fanjiatun Group.The study of fluid inclusions shows that the homogeneous temperature of fluids is 240~400 ℃，the salinity is 7.5%~10.5%，the density is 0.75~0.90 g/cm3. The metallogenic pressure is 6.40~15.75 MPa.And the metallogenic depth is 0.64～1.60 km.It has the characteristic of epithermal mineralization and medium-high metallogenic temperature mineralization.H-O isotope analysis results show that δ18O values of fluids from fluid inclusions in quartz vary from 5.40‰ to 6.86‰，δD values of quartz from the ore change from -103.1‰ to -100.0‰，indicates that the water was derived mainly from mixed meteoric and magmatic water.Integrating the geological features of the region，orebody characters and analysis results，this paper comes to the conclusion that this deposit is of the medium-high temperature，closely related to the invasion of granite and the metallogenic age of the Ailin gold deposit is early Yanshannian，it was formed in the transition from the collision closure of Petro-Asian Ocean to the subduction of Pacific Plate.
A gold mining area in Guangxi is located in the middle of Dayaoshan ore belt.Due to the exhausted mining of shallow minerals，the gold deposit is faced with the dilemma of resource exhaustion.From 2013 to 2015，relevant departments have successively carried out geological survey in this gold mining area，but these work only focused on the geological phenomena found on the surface，and did not consider the tectonic distribution closely related to mineralization，which could not meet the requirements of deep prospecting. According to the characteristics of high polarizability and low resistivity of metallogenic types in this area，and in order to meet the exploration requirements of deep prospecting，double frequency induced polarization（IP） method was selected to carry out a series of exploration work.The method of this work mainly includes the gradient induced polarization and the IP sound.According to the geological data，the wide distribution of carbonaceous rocks in the area makes the overall resistivity low，which on the one hand improves the probability of finding anomalies and is conducive to the search for gold deposits，on the other hand，increases the distribution range of abnormal bodies and interferes with the differentiation of ore-induced anomalies and the further narrowing of the prospecting target area.In this paper，by focusing on the middle or high polarization IP anomaly areas and combining with the low resistivity structural belt，the preliminary delineation of the prospecting target area is carried out.Then，IP sounding verification is carried out for the main anomaly areas and structural zones. Firstly，four IP anomalies were obtained and five structural zones were divided by the apparent amplitude frequency and the apparent resistivity.The results show that the anomalous No.1 coincides well with the structural zone No.1，both of which show a strip-like anomaly along the east-west direction，which is consistent with the predicted main ore tectonic trend.It is speculated that the anomaly is caused by the carbonaceous strata and metal sulfides around the fault zone or fracture zone，and the possibility of gold-bearing deposits in this area is very high.The anomalous No.2 is located in the intersection zone of the structural zone No.2 and the structural zone No.4. It is speculated that there are carbonaceous strata and metal sulfides in this area，and the possibility of gold deposits is high. The anomalous No.3 is located at the intersection of the structural zone No.3 and the structural zone No.5，and tends to extend northward. It is presumed that the anomaly is mainly caused by carbonaceous strata，and the possibility of gold deposits is general.There is no control of the corresponding structural zone in the anomalous No.4 area，so it is impossible to determine the prospecting prospects of the anomaly.According to the exploration results above，3 main prospecting targets were finally delineated.By comparing with inversion of the IP souding and later drilling data，the guiding significance of dual-frequency IP method for prospecting in this gold mining area is verified，which provides a scientific basis for further geological exploration work，and also provides a design idea for carrying out related electrical work in the future.
With the general trend of tunnel construction in China towards large and super-large sections，the application of full-face blasting excavation method in tunnel excavation generally has the problems of poor contour forming effect，low trace rate of blasting holes and large under or over excavation.The technology of full section blasting with pre-arranged layer and the technology of detonating peripheral hole with triangular lap of detonating cord can effectively solve the above problems and achieve good contour forming effect.The two kinds of blasting modes are introduced and compared，and the corresponding engineering application conditions are given in this paper.The advantages of the full section blasting technology with pre-arranged layer are analyzed，and the calculation formula for the parameters of the pre-arranged layer is given.The detonating mechanism of triangular lap of detonating cord is analyzed.The theoretical calculation of the blasting time is calculated，and as a result,the detonation signal can be transmitted to the whole blasting network in 5 ms，and the maximum detonating time difference between adjacent blast hole is less than 1ms.Based on the Dong Tianshan tunnel project，the field tests of two kinds of blasting modes have been carried out.The results show that both modes can effectively control the contour of the excavation section，improve the hole trace rate and reduce the over excavation.The applicable conditions of the two modes are as follows：The technology of full section blasting with pre-arranged layer can be used under the good condition of Ⅳ class surrounding rock and above grade Ⅲ surrounding rock；The technology of detonating peripheral hole with triangular lap of detonating cord can be applied under the poor condition of Ⅳ class surrounding rock and Ⅴ surrounding rock.The results can provide reference for similar projects.
Aiming at the problems of excessive blasting vibration and impact，high bulk rate，large vibration and blasting hazard effects in the process of deep hole lateral collapse blasting in underground mining，ANSYS/LS-DYNA software based on ALE algorithm is adopted in this paper.The program established a numerical model for the blasting of air-deck charge structures with four different air column lengths and different charge amounts.Firstly，using the initial impact pressure theory analysis，theoretically deducing the stress at different distances from the charging section，the stress peak is increased at the charging section，reduced at the air section，and the stress distribution in the middle of the air section is superimposed and analyzed.Then，using ANSYS/LS-DYNA software，the explosion stress field in the rock mass and the free surface of the collapse is numerically simulated when the charge structure is blasted.It shows that when the charge is the same within a certain engineering range,the effective stress decreases with the increase of the length of the air column.When the length of the air column is the same，the larger the charge is，the larger the effective stress is.The peak value of the stress appears to be the largest at the charging section，and it is reduced at the air section.The law of minimum stress in the middle is basically consistent with the theoretical analysis.By analyzing the effective stress peaks of the four air-deck charge models，it is obtained that within a certain engineering range，the effective stress decreases with the increase of the length of the air column in the case of the same charge.When the air column length is the same，the larger the charge，the greater the effective stress.The longer the length of the air column，the longer the length of the air column，the more stable the effective stress distribution，and the more uniform the explosion energy distribution.By extracting the effective stress peaks of the key elements on the free surface of each scheme，the effective stress peak curve was drawn，and the Von Mises yield criterion is used to judge whether the rock is damaged，and the vibration response speed of the particle on the free surface of the collapse is reflected.The effective peak of the unit on the surface and the peak of the unit synthesis speed was compared to select the best air-deck charge structure.
The underground mining of the mine has formed a large number of goaf groups，when these goaf groups reach a certain scale，it is likely to generate large-scale catastrophic ground pressure activities，and cause huge losses.Therefore，the stability analysis of the goaf group system is of great significance for the safe production of mines. In order to study the catastrophic instability of the goaf group system，the roof and the pillar are simplified as an elastic plate and a Poynting-Thomson body with creep damage under long-term loads，respectively.Considering the combined effect of horizontal and vertical loads，the catastrophic instability model of roof-pillar system in goaf group is established by combining rheological theory with swallowtail catastrophe.Due to the creep damage and weathering of the pillar，the effective support area of the pillar is gradually reduced，the center subsidence of the roof is gradually increased.When the center disturbance of the roof is increased to a certain value，the connection type of the roof is changed from fixed end to simple support，the stage when the connection type of the roof is fixed end is named the first stage.When the center disturbance of the roof is then increased to another value，the connection type of the roof is changed from simple support to free end，the stage when the connection type of the roof is simple support is named the second stage.And the stage when the connection type of the roof is free end is named the third stage.When the effective support area of the pillar is reduced to a certain value，the catastrophic instability of the model will happen.Supposed the model is in the first stage，the center subsidence of the roof when the catastrophe happens was calculated by using swallowtail catastrophe theory. By combining the rheological theory the stage when the catastrophe of the model happens can be judged，and then the ratio of pillar effective support area to roof area when the catastrophe happens was calculated.Finally the time from the start to the occurrence of catastrophe can be calculated by using the rheological theory.According to the ratio of pillar effective support area to roof area，the criterion for the catastrophic instability of the model was drawn from the calculation results，which provides a basis for the safe mining of the pillar.It is validated with the project example of the Panlong lead-zinc mine in Guangxi.The settling time of the goaf group system is consistent with the actual situation，which verifies the reliability and practicality of this model.The influence of horizontal loads，roof size，roof bending stiffness，roof thickness，vertical loads and initial elastic modulus of the pillar on the stability of the goaf group system is studied，which provides a new idea and method for the stability analysis of the goaf group system.The research shows that when roof size and vertical loads increase，the center subsidence of the roof gradually decreases and the ratio of pillar effective support area to roof area gradually increases when the catastrophe happens，the settling time of the goaf group system gradually decreases.When lateral pressure coefficient，roof bending stiffness and roof thickness increase，the center subsidence of the roof gradually increases and the ratio of pillar effective support area to roof area gradually decreases when the catastrophe happens，the settling time of the goaf group system gradually increases.When initial elastic modulus of the pillar increases，the center subsidence of the roof has no change and the ratio of pillar effective support area to roof area gradually decreases when the catastrophe happens，the settling time of the goaf group system gradually increases.
Sandy pebble soil has been widely used in engineering applications，such as railway subgrade，high earth-rock dams，bridge piers due to its excellent compaction performance and strong water permeability.At present，the research on the mechanical properties of sandy pebble soil at home and abroad mainly focuses on： （1）The dynamic deformation strength characteristics under complex stress state； （2）The effects of different density and water content on the mechanical parameters； （3）The simulation software to reflect the mechanical failure phenomenon of sandy pebble soil and calculate the mechanical parameters.The instability of rock mass is mainly caused by the slippage of rock mass along the failure surface under shear stress，but there was no research on shear rheological properties of sandy pebble soil at home and abroad.Shear rheological tests on sandy pebble soil under different normal stresses was carried out，and mechanical analysis and shear rheological model research were conducted based on experimental data to provide scientific analysis for the stability of sandy pebble soil engineering，thus ensuring long-term safety of sandy pebble soil engineering operations.The specific process of the test was to carry out the shear rheological test of the sandy pebble soil by the stepwise incremental loading method the normal stress of 0.025 MPa and 0.0375 MPa were applied to the two sets of samples，when the stability was stable for more than 24 h.Then the shear stress was applied from the low to the high grading time.When the displacement of the rheology within 24 h was not more than 0.001 mm，the deformation was considered to be relatively stable，and the next-stage shear stress can be applied. Did this until the test piece breaks. The RYL-600 rock shear rheometer recorded the rheological data for the entire process. Some classical viscoelastic models were used to simulate and compare the rheological curves before the accelerated rheology under 0.025 MPa normal stress and 0.203 MPa shear stress. It was known that the five-element viscoelastic model has an accurate simulation on stage before accelerated rheological transformation of sandy pebble soil. Because the accelerated rheological phase highlights the plastic properties of the rock，a new model obtained by connecting the five-element viscoelastic model and the VR viscoplastic model in series was used to fit the accelerated rheological results of the sandy pebble soil. Based on experimental data and analytical simulations，the following conclusions can be drawn： （1）Under the action of low shear stress，sandy pebble soil undergone instantaneous elastic deformation，initial rheological phase with decreasing speed，and constant steady rheological phase.When the shear stress of the sandy pebble soil exceeded its long-term strength，the rheology will continue to develop into an accelerated rheological failure stage. The magnitude of long-term shear strength increased with increasing normal stress.The reason was that the greater the normal stress，the higher the frictional force on the failure surface. （2）Through simulation comparison and analysis，it was found that the viscoelastic-plastic model obtained by connecting the five-element viscoelastic model and the VR viscoplastic model in series had a good fitting effect on the whole process rheological curve of sandy pebble soil.And the instantaneous elastic modulus tended to decrease linearly with the increase of shear stress. Although the viscoelastic shear modulus fluctuated，it was stable within the range of 1~5 MPa/mm. （3）The discrete nature of the particles and the randomness of the geometric distribution of the pebble also had a certain influence on the mechanical properties of the sandy pebble soil. In the future research，new numerical processing methods and simulation software should be adopted to characterize these important parameters，and analyze the specific effects of these parameters on the mechanical properties of sandy pebble soil.
The area of Chinese permafrost accounts for about 21.5 percent of the land area，ranking third in the world，and the permafrost area at high altitude accounts for about 80.6 percent of the permafrost area in China.Under the guidance of the national grand strategy，infrastructure construction in these areas has been greatly developed these years，but at the same time，the special geographical environment of the cold region puts forward a new test for the safety，stability and durability of rock mass engineering.In order to reduce the occurrence of engineering accidents and ensure public safety，it is of great significance to figure out the connotation differences and research progress of the freeze-thaw damages of rock and rock masses.By referring to the latest research results in the field of rock and rock masses freeze-thaw damage，the differences between rock and rock masses freeze-thaw damage are clearly defined，and the research status of freeze-thaw damage of rock and rock masses is systematically summarized and sorted out from three aspects：Physical and mechanical properties，freeze-thaw damage theory，constitutive model.It is found that the freeze-thaw damage mechanisms of rock and rock masses are remarkably different due to the various internal structures，spatial scales and distributions of fractures，and the corresponding criterions for damage evaluations are also different.From the perspective of connotations，the damage of rock results from the formation of microcrack and belongs to the microscopic scope（with a scale of millimeter or less），but the damage of rock masses is mainly influenced by fractures（with a scale of centimeter or more）and falls into the macroscopic scope.The current studies related to the freeze-thaw damages primarily focus on the intact rock blocks，and few researchers investigate the rock masses containing macroscopic fractures.Rock failure is due to the combined action of the frost heaves of in-situ and migratory water，and therefore the constitutive model of rock freeze-thaw damage is mainly built in the perspective of frost heave forces and fatigue damages.In the future，the influences of factures should be pay more attention.Starting from the microscopic scales，the mechanisms of water migrations and frost heaves and the laws of interaction in microcracks and fractures under the process of freeze-thaw cycles should be analyzed by laboratory experiments.Meanwhile，the constitutive model of freeze-thaw damage of the large-scale rock masses should be built by the numerical simulation and field tests.In this way，the evaluation system of freeze-thaw damage of rock and rock masses in cold regions could be formed.
As a complex natural medium，rock has formed cracks with different geometrical sizes and spatial combination characteristics in its interior after a long process of geological tectonics，which seriously affects the physical and mechanical properties of rock.Therefore，the study on crack initiation，propagation and penetration of rock materials and rock-like materials with cracks is of great significance for practical engineering.In order to investigate the strength and failure characteristics of the rock with zigzag fissure under uniaxial compression,the rock-like specimens are made by mixing C42.5 portland cement，fine sand，and water at a mass volume ratio of 2∶2∶1.The uniaxial compressive strength of this material is between 30~60 MPa，belonging to the sub-hard rock，which can represent the fracture behavior of most rocks in nature.The zigzag fissures are created by inserting aluminum shims into cement mortar paste and removing them during curing.Finally，the tooth-shaped specimens with different crack dip angle （β） and fluctuation angle （α） were obtained.The uniaxial compression test were conducted through rock mechanical servo test machine and loading process，crack initiation were observed and recorded by the camera.The test results show that：（1） There are three types of cracks observed,which are tensile cracks，shear cracks and tensile-shear cracks，and the failure modes of the specimen can be classified into three categories,that is A （tensile failure），B （shear failure），and C （compound failure）. For β∈（0°，30°），tensile wing crack is initiated from the tips of fissure which lead the flawed specimens to fail,naming A mode. For β∈（45°，60°），shear crack is observed in all flawed specimens,naming B mode.Tensile-shear compound failure (B mode)is observed in the specimens with β=75° and 90°. The inclination angle strongly affects failure modes，while the undulating angle seem to play only a minor role with respect to failure characteristics of specimen. （2）When the dip angle is small，the stress-strain curve of the specimen is multi-peak curve.With increasing of inclination angle，the stress-strain curve gradually transform to single-peak shape，and the post peak curve shows ductility weakening and brittleness enhancement.The residual strength curve of the specimens indicate that particle friction play a major role for residual strength under uniaxial compression.However，for the specimen with same inclination angle，the stress-strain curves for different undulating angles are roughly the same.（3）The lowest equivalent peak strength of the specimens is normally observed when β=30°. When the undulating angle is the same，the equivalent peak strength of specimens decreases as inclination angle increases from 0° to 30°，and increases for inclination angle α>30°, while the influence of the fracture undulation angle on the equivalent peak strength of specimens is smaller than the dip angle of fracture.
Sanshandao gold mine is located in the Laizhou Bay， eastern China.Its north and west sides are bordering the Bohai sea， only the southeast side is connected to the land.The mining operations are below the sea level， so the sea water is the potential threat to the mine.In order to predict and prevent water inrush disaster， it is important to identify the mine water source and determine the mixing ratios.In view of the identification of water source in mine tunnel， domestic and foreign scholars have done a lot of research.At present， the methods of mine water source identification are neuron network method， based on entropy weight-fuzzy variable set theory， clustering analysis， distance discriminant analysis and Fisher discriminant method.These methods can make a good distinction for water with simple composition， and are only qualitative identification for the composition of the complex water source， and there is no quantitative determination of mixing ratios of the mine water.Based on hydrogeochemical and isotopic analysis， the method of principal component analysis （PCA） was used to identify the mine water sources （seawater， 375-20 Mg， freshwater and 320-7 Ca） of Sanshandao gold mine and established the mixing model of mine water.The 375-20 （Mg） and 320-7 （Ca） are both brine but have different hydrochemical characteristics.The 375-20 is rich in Mg and the 320-7 is rich in Ca.The first， the second and the third components of the PCA method explained 88% of the information of the water samples， so the water sample can be represented by these three principal components.The end-members mixing ratios were calculated by the maximum likelihood method and the evolution rules of mine water were analyzed according to the calculation results.Unlike the traditional method， the maximum likelihood method holds that the end-member concentration is not a fixed value， but a change in time and space， and the influence of mining on the end-member can be effectively reflected by this method.The research shows that the method can effectively identify the water sources and calculated the mixing ratios.The seawater is the main component of mixed water and for the entire mine the proportion of the seawater fluctuated around 50% every year， the proportion of 375-20（Mg） and freshwater fluctuated around 20% and the 320-7（Ca） flucated around 10%. At -510 m sublevel， the mine water has a high proportion of seawater. At most of the water sites which are located between the prospecting lines 1660 and 2230，the proportion of seawater are more than 50%， especially at 510-2， the highest proportion is 77%. The main range affected by fresh water is 465 m sublevel and above. F3 fault is greatly affected by the mining， and the proportion of seawater of sites around which fluctuate greatly， so the monitoring of F3 fault needs to be strengthened.
Due to the using of large-scale mining equipment and the improvement of production management level in recent decades，long-term mining has led to the depletion of shallow mineral resources. Because of the complex geological conditions and high ground stress in deep mining，high-energy rock burst，earthquake，large-area goaf instability and other dynamic disasters are more likely to occur in the process of deep mining.Moreover，these geological hazards are difficult to accurately predict and prevent by traditional monitoring techniques.Micro-seismic monitoring technology can monitor micro-seismic events in the form of elastic waveforms released by rock mass during deformation and fracture in real time.It can also determine the location and energy parameters of micro-seismic events，so as to evaluate the safety of rock mass activity and stability.This is the main monitoring means of dynamic disasters in existing mines，and has been widely used in engineering fields with high risk of rock burst.The mining depth of Linglong gold mine in Shandong has exceeded 1 000 meters，and a micro-seismic monitoring system has been built in the deep part of the mine.Layout of network is the first and most important part of the construction of micro-seismic monitoring system，and it is the key factor affecting the effect of micro-seismic monitoring.Generally，that is need to be focused on are technology and economy factors.Technology is feasible to ensure the accuracy of monitoring data within the scope of system monitoring.Economy is reasonable to ensure that equipment and construction costs are reasonable.Due to the complexity of underground engineering，the layout of micro-seismic monitoring network is greatly limited，so it is usually necessary to compare several schemes to select the most suitable one.However，because the program optimization of micro-seismic monitoring system is a comprehensive evaluation problem involving multiple indicators，the traditional empirical analogy method is more subjective and difficult to achieve quantitative judgement.Based on the principal component analysis （PCA），a comprehensive optimization analysis model for micro-seismic monitoring network was established.First，a scientific and reasonable evaluation index system needs to be established.When determining the evaluation index，the principal component analysis can eliminate the influence of the correlation among the indicators，and does not need to consider the independence of the indicators.At the same time，it can simplify the data structure of the evaluation index and transform it into a few comprehensive indicators.Therefore，it is necessary to fully and comprehensively consider the various influencing factors in the system construction and operation stage，and try to select more evaluation indicators to make the evaluation results more comprehensive and accurate.Based on the actual situation of the construction and operation of the micro-seismic monitoring system in the Dakaitou mining area of Linglong gold mine，and combined with the evaluation parameters of previous related projects，eight indicators were selected from two aspects of economic and technical conditions to build a comprehensive evaluation index system.After the calculation of the model，eight original indicators were replaced by two new composite indicators，and the latter included about 91.9% information of the original data，which greatly simplifies the data structure of the scheme evaluation.Finally，based on the difference of the original data itself，the information contribution rate is used as the weight coefficient of the new comprehensive index，which avoids the error of subjective weight.It is a more scientific and simple weighting method.The comprehensive evaluation value of each scheme is calculated，and the scheme Ⅲ with the comprehensive evaluation value of 0.71 was the optimal scheme.The principal component analysis model provides a concise and effective comprehensive evaluation method for the optimization of micro-seismic monitoring network schemes.
Presently，the mines in domestic and foreign had been on the stage of deep mining.The high ground stress characteristics emerged and frequent dynamic geological hazards of mines happened，such as rock burst，which increased the difficulty of mining deep mineral resources.The rock bolt，anchor-mesh and other hard support which were used in shallow mines cannot achieve ideal governance effect，at the same time repair rate and maintenance cost was also high.Hence，it was imperative to carry out the study of deep mine destressing technology.This paper mainly introduced the destressing theory and destressing technology，summarized the current main destressing methods at home and abroad，and revealed the advantages and disadvantages of existing destressing methods.On this basis，some suggestions were put forward for the research methods and future research direction of destressing technology.Destress is one of the most effective ways to solve the high ground stress concentration in the deep part of the mine.Its basic principle was to improve the stress and energy release in the local surrounding rock by certain technical means，reduced the stress and energy concentration and the possibility of the instability of the deep rock mass.At present，the main destressing technologies at home and abroad include hydraulic destressing，borehole destressing，excavation destressing groove or destressing roadway and blasting destressing.The advantage of hydraulic destressing lied in increasing pore water pressure of rock mass and reducing effective stress and shear strength of rock mass，which was conducive to rock fracture expansion.However，the water injection pressure was relatively small，so good destressing effect cannot be achieved in hard rock area.The design of borehole destressing took fewer parameters into consideration and the parameters can be easily determined.However，the destressing of boreholes has a small range of influence.To achieve the desired effect of destressing，the number of boreholes was large，the construction time was long，and the construction schedule was also affected.The destressing groove or destressing roadway shall be determined in the direction of excavation and the distance from the high stress area.When the distance was too large，the destressing effect cannot be achieved.When the distance was too small，the size of destressing groove or destressing roadway was larger，which will lead to more obvious fracture and deformation of rock mass and is not conducive to rock mass stability.The blasting destressing process was simple，the effect was good，and the disturbance to the shallow surrounding rock was small.However，there were few studies on the mechanism of rock mass disturbance at present，and it was difficult to determine the influence range of blasting destressing pressure.The determination of reasonable and feasible destressing methods and parameters was the precondition and foundation for the field destressing. Similar material simulation and numerical simulation are the main methods for the research of destressing methods and parameters.The physical simulation can basically satisfy the similarity of geometric shape and mechanical parameters，but cannot achieve the simulation of factors such as ground stress，pore water pressure and structural surface，resulting in the deviation of the simulation results.The numerical simulation was relatively convenient and intuitive，and can simulate any mine engineering activities，which was widely used in determining the optimal parameters.Therefore，the main research direction of future pressure relief technology was to use numerical simulation method and combine various destressing methods to deal with complex geological conditions.
The filling mining method has the advantages of preventing and controlling the collapse of the empty area，slowing down or avoiding surface subsidence. However，when filling deep ore bodies，the requirements for filling quality are becoming higher and higher.Due to the difference between the filling processes，there are technical problems in the filling process of the mine，including the problem of the topping in the cement filling. The effect of the ceiling in the goaf or the empty area directly affects the supporting effect of the surrounding rock.Due to the poor filling and filling effect，there are still a few centimeters to several tens of centimeters of gaps between the upper cementing surface of the filling body and the top plate.Due to the existence of this gap，the surrounding rock may collapse and，in severe cases，may even cause the upper rock mass to collapse, forming a subsidence on the surface.In the test，the whole tailings were used as the filling material，according to the slurry concentration of 65%，70%，75%，80%，the bentonite content was 0，5%，10%，15%，and the ratio of lime to sand was 1∶4, 1∶6，1∶8，1∶10，design three factors and four levels，a total of 16 orthogonal experiments. From the experimental observation data，when the dosage is 0，the total bleeding rate of the slurry is 5.6%~24.3%； when the dosage is 5%，the total bleeding rate is 5.2%~23.8%； when the dosage is 10%，the total bleeding rate is 3.5%~15.3%； when the dosage reaches 15%，the total bleeding rate of the filling slurry is reduced to 1.1% to 9.0%.The results show that the influence of slurry concentration on total bleeding rate was the most influential，then bentonite was the second and cement-sand ratio was the least.The dynamic bleeding process of slurry have two stages with early rapid bleeding stage and late stable bleeding stage. And the duration of the two stages is different under different proportion conditions. From the dynamic bleeding process，the most important factor influencing is bentonite content，but the concentration of slurry and the cement-sand ratio are small than bentonite content at the dynamic bleeding rate.
In case of a copper mine in Xinjiang，the overflow run muddy is serious，the tailings’ utilization ratio for fillings was low，this affects the efficiency of work cycle in mine，meanwhile，the processing costs of overflow remain high.Solving the settlement problem of tailings will lay a good foundation for the construction of environmental friendly and efficient mine.In order to solve the problem，this paper study the grain degree and surface shape of whole tailings，as well as slurry initial concentration.With the aid of laser diffraction particle size analyzer and electron microscope scanning，it is showed that the content of ultrafine tailings at -20 μm is 44.61%，and shape of the tailings are irregular，and the surface are rough.The gravity of fine tailings is difficult to overcome the sedimentation resistance，which is the main reason for the muddy overflow of vertical sand tank.The relationship formula of fitting between the tailings sedimentation height and time under the slurry initial concentration of 10%，15% and 20% were explored through experimentation.It was observed that the settlement curve of different concentrations showed a similar trend. The binding degree of tailings and polymeric flocculant chain is similar to that of receptor binding enzyme，so the Hill function is used to fit the sedimentation curve，the coefficient R 2 were all greater than 0.975.The fitting relationship indicates，under the same time T，the settlement height is proportional to the factor V max，inversely proportional to K and n.By useing the numerical analysis method，the relationship between slurry initial concentration and V max，K，n were studied，to find the peak value of C-V max，C-k and C-n fitting curves.It was finally derived that the optimal slurry initial concentration value is 16% to 17%.Then compared the sedimentation test value with the predictive value by fitting equation under the condition that slurry initial concentration is 16.5%，the results prove that this method could well predict the optimal slurry initial concentration range for the flocculation sedimentation of the whole tailings.The above experimental research and analysis provide guidance for the field production.By increasing adjustment facility and interlock the parameters date in the filling station control system，to maintain the value of slurry concentration in the range of 16% to 17%,it matching the optimum additive amount of flocculant for the whole tailings in vertical sand tank.After this series of measures，the overflow of vertical sand tank will be clarified，the tailings’ utilization ratio for the fillings could be increased.
Antimony-bearing gold ore is a kind of refractory gold deposit.Because gold is generally shown in microscopic particles wrapped in antimony，iron and arsenic sulfide，the general gold leaching method is not very effective in dealing with this mine.In views of the extraction difficulty of antimony-bearing gold ore，a new process based on the reduction and sulfur-fixing roasting and combination of beneficiation and metallurgy was proposed.Using ZnO and carbon as sulfur fixing agent and reductant，antimony sulfide is transformed to metal Sb and ZnS，and the gold is gathered in the former.Then the mixture is separated by mineral separation method.Gold enter the crude antimony powder following antimony.Crude antimony powder has been refined to obtain fine antimony powder，while zinc sulfide concentrate can be directly used in the smelting of zinc to produce metal zinc.The mechanism of the roasting process were investigated in detail，and the results show that overall reaction contained two steps.When the temperature is below 800 ℃，the main reaction are performed between Sb2S3 and ZnO to yield Sb2O3.Less antimony oxide is reduced and no more metal antimony is obtained.When the temperature is higher than 800 ℃，a large amount of the Sb2O3 is reduced to metallic antimony.The particle of antimony and zinc sulfide distributed respective without parcel.Both sulfur-fixing and reducing reactions are engaged completely，and with the increase of temperature，the sulfur-fixing rate and the production rate of metal antimony increased.The sulfur-fixing rate of ZnO and generation rate of antimony reached 98.96% and 92.99% respectively at 1 000 ℃.In a gravity separation and flotation test of the roasting product of Sb-bearing gold concentrate，Sb could be extracted with a direct recovery rate of 90.57%，while the grade of cured antimony and content of gold were 92.06% and 134×10-6，meanwhile，the sulfur-fixing rate reached 94.35%.So the new process is feasibility with the advantages of low temperature and low carbon，cleaning and environmental process.
Rational planning and management of ore quality is an important issue to improve the resource and economic benefits of the mine.Resources and quality control of ore should be run through all aspects of the entire production management process.In order to solve problems existed in ore blending for open-pit mine，such as long-time ore blending，low accuracy of planned results and not associated with truck dispatching system，the open-pit mine automation ore blending system was proposed.It is based on Mixed Integer Programming and would make the ore grade control in open-pit mine more accurately and rapidly，so rational mining and fine control of production targets for the open-pit mine automation ore blending would be achieved.It was put forward based on the current status quo of stope，exploration engineering data and resource model，on the premise of production quality control，and mixed integer programming algorithm is used as the theoretical method.This paper taking a large limestone open-pit in Anhui Province as research object.In the first place，thiessen polygon method was applied to estimation value and divide the ore blending model based on rock sample of blasthole and mine block model.Then a mixed integer programming model was presented according to the special ore blending requirements of muck piles in open pit mineto solve the optimization problem of ore blending.The model takes the minimum fluctuation of the ore grade as the objective function，and takes into account a variety of constraints，such as the muck sub-piles mining constraint，vehicle dispatching manner constraint，shovel car mining constraint，number of shovel car in each pile constraint，maximum grade of ore dumping constraint，minimum grade of ore dumping constraint .At last，the automatic ore distribution system of open pit mine is established based on iMine spatial database technology with C++ language programming in Visual Studio 2012，by solving the mixed integer programming model of open-pit ore blending by IBM ILOG CPLEX Optimization Studio， the open-pit ore blending optimization scheme of mine and truck dispatching can be achieved.The method was applied to Quanjiao Conch limestone mine，several months of practical application proved that this model is scientific and feasible.The ore blending method can output result in 1 s，and the maximum deviation of each index of ore blending fluctuates from the target value within the range of 1.5%，the average deviation of each index from the target value is less than 0.2%，and the coefficient of variation is less than 1%.It meets the requirement of mine grade deviation control，so it is of important significance for guiding the actual production of open-pit mine.
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