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Articles 2731 - 2760 of 4560
Full-Text Articles in Engineering
Csamt Phase Correction And Its Application In Detection Of Water-Accumulating Area Of Goaf In Coal Mine, Su Chao, Hou Yanwei, Wang Cheng, Li Dan
Csamt Phase Correction And Its Application In Detection Of Water-Accumulating Area Of Goaf In Coal Mine, Su Chao, Hou Yanwei, Wang Cheng, Li Dan
Coal Geology & Exploration
Magnetic field data of controlled source audio magnetotelluric method(CSAMT) is vulnerable to electromagnetic interference, and will lead to serious degradation of phase data quality. The affected phase data are corrected by referring to the high quality phase data of adjacent measuring points and combining the least squares fitting and interpolation method. Through forward simulation analysis, it is found that cubic polynomial interpolation is effective, not only can restore the variation characteristics of phase curve more accurately, but also involve the corrected phase data in the inversion calculation, so that the inversion results are more accurate and reliable. The method is …
Test Of Water Absorbent Resin For Disposal Of Waste Mud, Wei Meng, Qi Jinhui, Zhang Ningxin, Wen Jun
Test Of Water Absorbent Resin For Disposal Of Waste Mud, Wei Meng, Qi Jinhui, Zhang Ningxin, Wen Jun
Coal Geology & Exploration
In the course of engineering construction, a lot of abandoned mud is produced. How to properly handle these mud has received extensive attention. In this paper, the application of absorbent resin in waste mud treatment is studied by series of experiments. Compared with the common flocculants, the flocculation effect of absorbent resin is better, and the separation speed of waste mud solid liquid can be accelerated obviously. The water absorption rate of absorbent resin in the mud reaches 46.33 g/g, which can be incorporated into the mud to greatly reduce the water content and fluidity of the mud within 30 …
Concealed Riprap Detection Technology In Pile Foundation Engineering, Li Junjie, Ge Longjin, Zhang Honggang, Li Jianmin, Zhu Honglei, Li Guanhao
Concealed Riprap Detection Technology In Pile Foundation Engineering, Li Junjie, Ge Longjin, Zhang Honggang, Li Jianmin, Zhu Honglei, Li Guanhao
Coal Geology & Exploration
It is often necessary to use pile foundation to deal with soft soil foundation for the newly built gate station near the seawall. If there is a concealed riprap layer in the construction area, it will affect the construction progress of pile foundation and increase the construction cost. Furthermore, the spatial distribution characteristics of riprap also play a decisive role in the selection of pile foundation construction technology. In view of the blindness problem in using the drilling method to investigate the irregular concealed riprap, we adopt the comprehensive investigation technology combining the ground penetrating radar with the high density …
Fault Identification Technology Of Ant Attribute Optimization, Li Hongwei, Bai Xuelian, Cui Jingbin, Wan Zhonghong, Yuan Shihong, Chu Wanchang
Fault Identification Technology Of Ant Attribute Optimization, Li Hongwei, Bai Xuelian, Cui Jingbin, Wan Zhonghong, Yuan Shihong, Chu Wanchang
Coal Geology & Exploration
In the field of seismic geological exploration, the ant attributes is more and more widely used for rapid identification of fault system, and in the process of practical application, ant attributes based on 3D seismic data extraction are displayed either along strata slice(plan) or in section, the features of fault system and distribution characteristics of seismic events is not corresponding to the actual situation, the application effect is poorer, fault interpretation work is given priority to with manual interpretation backbone profile, unable to realize fault automatic tracking. In view of this widespread situation, this paper studies and analyzes the actual …
Analysis Of Factors Affecting The Automatic High-Frequency Induction Brazing Strength Of Pdc, Dai Yongbo
Analysis Of Factors Affecting The Automatic High-Frequency Induction Brazing Strength Of Pdc, Dai Yongbo
Coal Geology & Exploration
With the development of automation and intelligentization in manufacturing industry, the research on PDC bit brazing automation is one of the key development directions of bit production technology. In order to study the influencing factors and adaptation methods of welding strength in PDC automatic brazing process, PDC high frequency induction welding and shear strength comparison test were carried out by using PDC and alloy pillar as the base material through special tooling and test conditions. Combined with the shear strength experiment and the morphology of brazing surface of PDC high-frequency induction brazing, the effect of brazing filler alloys, fluxes, surface …
Combined Cbm Production Behavior And Development Strategy Of Multiple Coal Seams In Zhijin Block, Guo Tao, Gao Xiaokang, Meng Guixi, Xiao Cui
Combined Cbm Production Behavior And Development Strategy Of Multiple Coal Seams In Zhijin Block, Guo Tao, Gao Xiaokang, Meng Guixi, Xiao Cui
Coal Geology & Exploration
Aiming at the problems that the CBM layers are numerous and thin, it is difficult to develop it effectively in south China, on the basis of the actual production data of CBM wells in Zhijin block, the production characteristics and the influencing factors of gas production of the directional wells for co-extraction of different seams and the horizontal wells for thin seams were analyzed, and corresponding suggestions for CBM development were put forward. The analysis indicated that the gas production of co-extraction of different seams was quite different, was influenced by the liquid-supplying capacity of formation, the height of desorbing …
Application Of High Precision Gravity Survey In Detecting Mined-Out Areas Of Fushun Coal Mine, Huan Hengfei, Gao Tie, Zhao Haiqing, Zhao Weijun, Guo Canwen, Shi Bin
Application Of High Precision Gravity Survey In Detecting Mined-Out Areas Of Fushun Coal Mine, Huan Hengfei, Gao Tie, Zhao Haiqing, Zhao Weijun, Guo Canwen, Shi Bin
Coal Geology & Exploration
In order to find out the location, depth and distribution range of the mined-out areas in Fushun coal mine, and comprehensively considering the factors affecting the geophysical methods in the cities, the method of high-precision gravity survey was firstly used to study the mined-out areas in the area. Firstly, by analyzing the physical differences of the mined-out areas, a theoretical model was established for forward calculation and preliminarily studied on applicability of the gravity method. Then, a large-scale work of high-precision gravity survey was arranged in the study area, and through potential field separation,3D apparent density inversion and boundary identification …
Drainage Technology And Test Of Stratified Pressure Control With Four-Channels Of Cbm Well In Double Coal Seams, Pang Tao, Jiang Zaibing, Li Bingang, Du Xinfeng
Drainage Technology And Test Of Stratified Pressure Control With Four-Channels Of Cbm Well In Double Coal Seams, Pang Tao, Jiang Zaibing, Li Bingang, Du Xinfeng
Coal Geology & Exploration
Aiming at the problems of mutual interference between layers and serious damage in reservoirs in the production process of double-coal CBM wells, a four-channel stratified pressure control drainage technology was proposed, in the process of drainage, two coal seams were controlled in different pressure systems to achieve the purpose of stratified production and CBM well drainage device with four-channel packer, monitoring equipment, multi-channel tubing centralizer, roller sucker rod centralizer and auxiliary communication tube for double coal seams was developed. Field application test shows that the four-channel packer can achieve the isolation effect according to the needs, so that the two …
Table Of Contents, The Editors
Research And Application Of Casing Milling And Fishing Technology In Floor Comb-Shaped Directional Borehole, Guan Qiangsheng, Wei Hongchao
Research And Application Of Casing Milling And Fishing Technology In Floor Comb-Shaped Directional Borehole, Guan Qiangsheng, Wei Hongchao
Coal Geology & Exploration
In order to solve the problem that using the conventional strong-force rotary drawing process for borehole sticking accident in comb-shaped directional borehole in floor is not ideal, and using reverse thread drill pipe or strong twist cause big time and economic loss, through the calculation and analysis of the passing capacity of casing milling and fishing pipe in the curved hole, the technical parameters of casing milling and fishing, the sticking accident of floor comb-shaped directional borehole with the depth of 344 m in a coal mine in Henan Province was successfully solved. The application results show that the maximum …
Evaluation Of Coalbed Methane Drainage Effect For Multi-Target Seams In Jincheng Region, Yang Jianchao, Li Guihong, Liu Yuhui, Li Guofu, Wang Chaoshuai, Sun Tianyu
Evaluation Of Coalbed Methane Drainage Effect For Multi-Target Seams In Jincheng Region, Yang Jianchao, Li Guihong, Liu Yuhui, Li Guofu, Wang Chaoshuai, Sun Tianyu
Coal Geology & Exploration
The study of the multi-target seams drainage effect on coalbed methane wells has great value, including coal safe mining, underground gas control, determination of development technical indicators, single well production, rational division of development layer, efficient development of coalbed methane, and development of medium and long-term coalbed methane development planning. Taking Chengzhuang mine of Jincheng as an example, the sampling data of the extraction effect in the middle and late stages of development are compared with the original gas content of the adjacent wells to evaluate the extraction effect, and the main control factors affecting the drainage effect are analyzed …
Supporting Technology Of Roadway Crossing Fractured Zone Of Fault Under Dynamic And Static Load, Song Weihua, Di Chunlei, Deng Zhaorui
Supporting Technology Of Roadway Crossing Fractured Zone Of Fault Under Dynamic And Static Load, Song Weihua, Di Chunlei, Deng Zhaorui
Coal Geology & Exploration
The gateway 5303 encountered multiple normal faults during the driving in Changping mine of Jinmei Group. For the purpose that the gateway can pass through the faults safely and rapidly and ensure applicative methods and scope of supporting. So based on the principle of maximum principal stress and fracture damage mechanics of rock, the paper analyzes the crushing mechanism of the normal fault zone under dynamic and static load from macroscopic and microscopic perspectives. Then, the plastic failure model of fault zone was established, the normal fault sliding mechanism and supporting theory were combined to derive the expression of the …
Comprehensive Evaluation Technology And Application Of Grouting Reinforcement Effect For Broken Coal And Rock Mass, Wang Xiaolei, Ji Zhigang, Luo Wenqiang
Comprehensive Evaluation Technology And Application Of Grouting Reinforcement Effect For Broken Coal And Rock Mass, Wang Xiaolei, Ji Zhigang, Luo Wenqiang
Coal Geology & Exploration
Grouting reinforcement of broken coal and rock mass plays an important role in controlling the stability of surrounding rocks, and the grouting effect detection is an important link to ensure the grouting engineering to meet the requirements. The evaluation index was quantitatively analyzed by slurry filling rate method, mechanical parameter method, segmented water injection method, geological radar method, drilling television method and core inspection method. The comprehensive evaluation form of grouting effect was put forward, and the application research was carried out. The results show:The rate of filling slurry and coring was more than 90%; After grouting, the compressive strength …
Deformation Characteristics And Support Timing Of Deep High Stress Roadway, Geng Weile, Dong Ziwen, Guo Shengli, Pi Zikun
Deformation Characteristics And Support Timing Of Deep High Stress Roadway, Geng Weile, Dong Ziwen, Guo Shengli, Pi Zikun
Coal Geology & Exploration
The rock occurrence environment and structural characteristics determine its strength criteria, and affects the mechanical and deformation characteristics of surrounding rock. This paper relies on the deep replacement project of a mine in Yunnan, based on the rock strength criteria, and analyzes the mechanics and deformation characteristics of surrounding rock and the reasonable secondary support time of roadway to decrease the influence of the roadway support effect because of the obvious rheological properties present under high ground stress. The results showed that the min-average simulated deviations mf was generalized H-B criterion which was aimed at the sum of deviation absolute …
Fundamental Limits To The Transfer Of Energy Harvested From Ferroelectric Materials Under Shock Loading, Sergey I. Shkuratov, Jason Baird, Vladimir G. Antipov, Jay B. Chase
Fundamental Limits To The Transfer Of Energy Harvested From Ferroelectric Materials Under Shock Loading, Sergey I. Shkuratov, Jason Baird, Vladimir G. Antipov, Jay B. Chase
Mining Engineering Faculty Research & Creative Works
Ferroelectrics are capable of producing megawatt power levels under shock loading due to stress-induced phase transformations, resulting in depolarization of the ferroelectric materials. This power can be used for generation of high voltages, high currents, or ultrahigh-power electromagnetic radiation. The results are reported herein on an experimental study of limitations on energy harvested from shocked Pb0.99(Zr0.95Ti0.05)0.98Nb0.02O3 and PbZr0.52Ti0.48O3 ferroelectrics and transferred to external electrical systems. The experimental results indicate that one of the limits to the energy transfer is electric breakdown that occurs within …
Measurement And Simulation Study On Effective Drainage Radius Of Borehole Along Coal Seam, Wei Qin, Jialin Xu, Guozhong Hu, Jie Gao, Guang Xu
Measurement And Simulation Study On Effective Drainage Radius Of Borehole Along Coal Seam, Wei Qin, Jialin Xu, Guozhong Hu, Jie Gao, Guang Xu
Mining Engineering Faculty Research & Creative Works
A measurement study was conducted for the effective drainage radius of borehole along coal seam #9 of the Kaiyuan Coal Mine using the gas pressure method and gas flow method. The measurement results show that the effective drainage radius of borehole along coal seam #9 was 0.75 m, 27 days after drainage, and 1.5 m, 92 days after drainage. Experimental schemes were designed for the entire evolution of the stress in the coal mass around the borehole, and an experimental study on methane seepage in the coal mass around borehole was conducted. Fitting functions for the permeability of the coal …
Multilayer Pzt 95/5 Antiferroelectric Film Energy Storage Devices With Giant Power Density, Sergey I. Shkuratov, Jason Baird, Vladimir G. Antipov, Shujun Zhang, Jay B. Chase
Multilayer Pzt 95/5 Antiferroelectric Film Energy Storage Devices With Giant Power Density, Sergey I. Shkuratov, Jason Baird, Vladimir G. Antipov, Shujun Zhang, Jay B. Chase
Mining Engineering Faculty Research & Creative Works
A new type of energy storage devices utilizing multilayer Pb (Zr0.95Ti0.05)0.98Nb0.02O3 films is studied experimentally and numerically. To release the stored energy, the multilayer ferroelectric structures are subjected to adiabatic compression perpendicular to the polarization direction. Obtained results indicate that electrical interference between layers (10–120 layers) during stress wave transit through the structures has an effect on the generated current waveforms, but no impact on the released electric charge. The multilayer films undergo a pressure-induced phase transition to antiferroelectric phase at 1.7 GPa adiabatic compression and become completely depolarized, releasing surface …
Table Of Contents, The Editors
Trilinear Chart Classification Method Of Mine Water Hazard Type Based On Factors Of Water Recharge, Hu Weiyue, Zhao Chunhu
Trilinear Chart Classification Method Of Mine Water Hazard Type Based On Factors Of Water Recharge, Hu Weiyue, Zhao Chunhu
Coal Geology & Exploration
The results of the classification of hydrogeological types in coal mines are relatively inadequate to reflect the characteristics of water hazards such as water sources and water inrush channels. It is not very instructive to carry out water control work in coal mines starting from the basic elements of mine water hazard formation, this paper analyses the characteristics and harm degree of mine water hazard under different types of mine water sources, water inrush channels and their combination conditions, the water inrush source can be divided into 4 types according to its water-rich degree and supply capacity:weak supply of slow …
Analytical Solution For Surrounding Rock Of Circular Roadway Based On Generalized Smp Criterion Considering Seepage And Dilatancy, Pan Jiliang, Ren Fenhua
Analytical Solution For Surrounding Rock Of Circular Roadway Based On Generalized Smp Criterion Considering Seepage And Dilatancy, Pan Jiliang, Ren Fenhua
Coal Geology & Exploration
Based on the generalized spatially mobilized plane(SMP) criterion, considering intermediate principal stress, pore water pressure and dilatancy characteristics of surrounding rock, an ideal elastic-plastic model of roadway surrounding rock is established. According to the elastic-plastic theory, the unified analytical solutions of stress field, displacement field and radius of plastic zone under seepage flow are obtained. Then, the stress distribution of surrounding rock and the radius of plastic zone calculated by SMP criterion are compared with those calculated by Mohr-Coulomb(M-C) criterion, and the influencing factors such as pore water pressure and dilatancy angle of surrounding rock are analyzed. It is shown …
Identification Model Of The Independence Right-Fuzzy Variable Theory Of Water Inrush Source, Dong Donglin, Li Xiang, Lin Gang, Bian Jianling, Cao Chenglong, Wu Heng
Identification Model Of The Independence Right-Fuzzy Variable Theory Of Water Inrush Source, Dong Donglin, Li Xiang, Lin Gang, Bian Jianling, Cao Chenglong, Wu Heng
Coal Geology & Exploration
In the process of coal mining, mine water hazard accidents occur frequently. In order to find out the water source of mine water inrush quickly and accurately, and reduce the harm caused by mine water inrush to coal mine production, taking Zhaogezhuang mine as an example, and the method of combining independent weight coefficient with fuzzy variable theory was used to select six kinds of hydrochemical indexes of Na+, Ca2+, Mg2+, Cl-, SO42- and HCO3-, 20 sets of water sample data of Zhaogezhuang mine were analyzed and …
Micro Ct-Based Meticulous Characterization Of Porosity Evolution Of Coal In The Process Of Biodegradation, Dong Zhiwei, Guo Hongyu, Xia Daping, Liu Xile, Bai Yang, Zhao Guojun
Micro Ct-Based Meticulous Characterization Of Porosity Evolution Of Coal In The Process Of Biodegradation, Dong Zhiwei, Guo Hongyu, Xia Daping, Liu Xile, Bai Yang, Zhao Guojun
Coal Geology & Exploration
To explore the bio-permeability enhancing effect via methanogen treatment on different rank coals after anaerobic fermentation, micro-CT was used to analyze the change characteristics of pore structure of coal before and after biodegradation. At the same time, the adsorption characteristics of methanogens on the coal surface after anaerobic biodegradation were observed by scanning electron microscopy to analyze the reasons for the effect difference of biological transformation of different rank coals. The results show that the porosity and total throat length of the coal samples biodegraded increase and the connectivity of the pores is enhanced, it is indicated that coal samples …
Comprehensive Outburst Prevention Technology Of Outburst-Prone Coal Seam Uncovered By Crossdrift In Hongshan Coal Mine, Wang Beifang, Liang Bing, Zhang Jing, Chi Haibo, Huang Pujiang
Comprehensive Outburst Prevention Technology Of Outburst-Prone Coal Seam Uncovered By Crossdrift In Hongshan Coal Mine, Wang Beifang, Liang Bing, Zhang Jing, Chi Haibo, Huang Pujiang
Coal Geology & Exploration
Coal and gas outburst is a complex geo-dynamic disaster induced by a coal seam uncovered by crossdrift, threatens the safety and efficient production of coal mines seriously. For this, Hongshan coal mine was selected as engineering background to simulate mechanical response characteristics of surrounding rock during uncovering No.12 coal seam in a gas bursting hazardous zone with FLAC3D software. Then the outburst mechanism during uncovering a coal seam by a crossdrift was revealed, and comprehensive outburst prevention technology combining mine gas pre-drainage and improved metal skeleton was put forward. The results showed that the abutment pressure ahead of the …
Molecular Simulation Of The Influence Of Foam Fracturing Fluid Additives On Coalbed Methane Diffusion, Yang Zhaozhong, Han Jinxuan, Zhang Jian, He Rui, Lu Yanjun, Li Xiaogang
Molecular Simulation Of The Influence Of Foam Fracturing Fluid Additives On Coalbed Methane Diffusion, Yang Zhaozhong, Han Jinxuan, Zhang Jian, He Rui, Lu Yanjun, Li Xiaogang
Coal Geology & Exploration
Materials Studio(MS) software was used to establish a slit pore molecular model which considers the in-teractions among water-bearing coal, foam agent and foam stabilizer. Based on molecular diffusion theory, the diffusion ability of methane molecule respectively affected by four common foam agents and four foam stabilizers was calculated. Compared to original water-bearing coal, self-diffusion coefficient of coalbed methane(CBM) is reduced by 71.3%, 74.7%, 56.3%, 54.0% after adding foaming agents including sodium dodecyl sulfonate(SDS), sodium lauryl sulfate(SLS), sodium dodecyl benzene sulfonate(SDBS) and lycine respectively. Based on adding SDBS into water-bearing coal, the self-diffusion coefficient of CBM is further reduced by 63.2%, …
Reasons Of Low Yield And Stimulation Measures For Vertical Cbm Wells In High-Rank Coal, Jia Huimin, Hu Qiujia, Qi Kongjun, Liu Chunchun, Fan Bin, He Jun
Reasons Of Low Yield And Stimulation Measures For Vertical Cbm Wells In High-Rank Coal, Jia Huimin, Hu Qiujia, Qi Kongjun, Liu Chunchun, Fan Bin, He Jun
Coal Geology & Exploration
The CBM production is usually low and development effect is poor in China, which are mainly due to the poor adaptability of the stimulation measures to the geological conditions. This article, based on the low-yield reasons for vertical CBM wells in Zhengzhuang block in southern Qinshui basin, puts forth corresponding stimulation measures, analyzes the mechanism and the geological adaptability, optimizes the parameters of specific stimulation measures and carries out pilot test. The research and practices show that in deeply buried area, fractures are difficult to form, and re-fracturing technology can make the fracture turn and increase the crack length, which …
Estimation Method And Application Of Free Gas Content In Coal, Jiang Wenping, Zhang Qun, Zhang Peihe, Dong Mintao, Tian Xinjuan, Ru Ting
Estimation Method And Application Of Free Gas Content In Coal, Jiang Wenping, Zhang Qun, Zhang Peihe, Dong Mintao, Tian Xinjuan, Ru Ting
Coal Geology & Exploration
In order to study the distribution characteristics of free gas content in coal reservoirs, based on the understanding that free gas mainly exists in coal pores, the estimation method of free gas content is optimized. Based on the test data of coalbed methane arameters of 42 groups of coals with different ranks from lignite to anthracite in typical coal-bearing areas of China, the free gas content of different coal samples were calculated by using the optimized method of free gas content estimation, and compared with the results of desorption gas content. The results show that the ratio of free gas …
Analysis On The Type Of Reservoir Pressure Drop And Drainage Control Of Coalbed Methane Well In The Southern Block Of Shizhuang, Yi Yongxiang, Tang Shuheng, Zhang Songhang, Yan Xinlu, Wang Kaifeng, Dang Feng
Analysis On The Type Of Reservoir Pressure Drop And Drainage Control Of Coalbed Methane Well In The Southern Block Of Shizhuang, Yi Yongxiang, Tang Shuheng, Zhang Songhang, Yan Xinlu, Wang Kaifeng, Dang Feng
Coal Geology & Exploration
In order to fully understand the reservoir pressure variation characteristics of coalbed methane wells in the southern block of Shizhuang and based on the analysis of reservoir geological parameters and the analysis of actual production data, the reservoir pressures of different types of production wells are analyzed. The specific analysis of the drainage control and reservoir sensitivity effects is also carried out based on the abnormal wells. The results showed that the reservoir lamination of coalbed methane wells in the southern block of Shizhuang can be divided into three types, namely type of rapid pressure drop, type of medium-term stability …
Development And Test Of Self-Adjusting Deflected Wellhead Sealing Device For Coalbed Methane Wells, Pang Tao
Development And Test Of Self-Adjusting Deflected Wellhead Sealing Device For Coalbed Methane Wells, Pang Tao
Coal Geology & Exploration
In order to solve the problem of fluid and gas leakage in coal seam gas well, a self-adjusting deflected wellhead sealing device suitable for coal seam gas wells is developed. The device consists of three parts:Smooth rod sealing box, self-adjusting deflected part and lower sub. The self-adjusting deflected part is a smart combination of universal joint and high pressure flexible rubber tube, which makes the sealing box and the polished rod always keep good concentricity. Practical application shows that this kind of polished rod sealing device has reliable sealing performance, simple structure and the prospect of popularization and application.
Experimental Study On Contact Angle And Pore Characteristics Of Unsaturated Loess, Jing Yanlin, Wang Hao, Tao Chunliang, Yang Lina, Liu Jianwei, Wen Xin
Experimental Study On Contact Angle And Pore Characteristics Of Unsaturated Loess, Jing Yanlin, Wang Hao, Tao Chunliang, Yang Lina, Liu Jianwei, Wen Xin
Coal Geology & Exploration
Contact angle and pore size are important factors affecting soil wettability, permeability and capillarity. In order to further understand the capillary characteristics and permeability of unsaturated loess, the contact angle test and mercury intrusion test of unsaturated loess were carried out. The relationship between pore size and contact angle was analyzed in details. Moreover, the variation of pore and contact angle with depth was discussed. It is found that the contact angle of loess in the dry state is higher than the contact angle of loess in the natural state; as the depth of the formation increases, the contact angle …
Influence Of Loading Rate On The Fracture Characteristics Of Large-Size Specimen, Chen Juntao, Li Ming, Cheng Binbin, Yang Fan, Men Huili, Shao Zhujuan
Influence Of Loading Rate On The Fracture Characteristics Of Large-Size Specimen, Chen Juntao, Li Ming, Cheng Binbin, Yang Fan, Men Huili, Shao Zhujuan
Coal Geology & Exploration
According to the high mining speed of modern mines in China, the fracture characteristics of rock mass under different uniaxial loading rate was systematically analyzed. Based on the geological condition of deep rock mass in Jining area, the optimum mortar composed of 425 Portland cement, sand with particle size less than 2 mm, gypsum, water and high efficient water reducer was used, which had the mechanical properties similar to real rock mass was ascertained. Applying the triaxial rock test system of coupled stress-seepage and PCI-2 real-time monitoring system of AE, the fracture process of specimens of large size under biaxial …