首页期刊导航|矿业科学技术学报（英文版）
期刊信息/Journal information
矿业科学技术学报（英文版）
矿业科学技术学报（英文版）

骆振福

双月刊

2095-2686

journal@cumt.edu.cn

0516-83885569

221008

江苏省徐州市中国矿业大学内

矿业科学技术学报（英文版）/Journal International Journal of Mining Science and TechnologyCSCDCSTPCD北大核心EISCI
正式出版
收录年代

    In-situ observation and modeling approach to evolution of pore-fracture structure in coal

    Hongwei ZhouZelin LiuJiawei ZhaoBocen Chen...
    265-274页
    查看更多>>摘要：The characterisation of the pore-fracture structure(PFS)and its evolution in coal during mining are essential for preventing gas outbursts and improving gas extraction efficiency.In this study,the evolution of the PFS in coal samples under the condition of mining stress was directly captured in situ by combi-nation of the mechanical testing system with high-precision visualisation nuclear magnetic resonance equipment.A fractional derivative model was established to describe the relationship between stress and porosity based on experimental results of the PFS under different stress states.The results showed that with an increase in the deviatoric stress,the adsorption pore content increases rapidly initially and then increases slowly or remains unchanged;the seepage pore and fracture(SPF)content decreases initially and then increases.The SPF compressibility coefficient decreases with an increase in the devia-toric stress.The fractional derivative model can accurately describe the stress sensitivity of the SPFs at the pre-peak stage,thus providing a new approach for accurately characterising the seepage characteristics of coal reservoirs.
      原文链接:
    • NETL
    • NSTL
    • 万方数据
    • 维普

    Experimental study on failure characteristics of single-sided unloading rock under different intermediate principal stress conditions

    Chongyan LiuGuangming ZhaoWensong XuXiangrui Meng...
    275-287页
    查看更多>>摘要：Investigation of unloading rock failure under different σ2 facilitates the control mechanism of excavation surrounding rock.This study focused on single-sided unloading tests of granite specimens under true tri-axial conditions.The strength and failure characteristics were studied with micro-camera and acoustic emission(AE)monitoring.Furthermore,the choice of test path and the effect of σ2 on fracture of unload-ing rock were discussed.Results show that the increased σ2 can strengthen the stability of single-sided unloading rock.After unloading,the rock's free surface underwent five phases,namely,inoculation,par-ticle ejection,buckling rupture,stable failure,and unstable rockburst phases.Moreover,at σ2≤30 MPa,the b value shows the following variation tendency:rising,dropping,significant fluctuation,and drop-ping,with dispersed damages signal.At σ2≥40 MPa,the tendency shows:a rise,a decrease,a slight fluc-tuation,and final drop,with concentrated damages signal.After unloading,AE energy is mainly concentrated in the micro-energy range.With the increased σ2,the micro-energy ratio rises.In contrast,low,medium and large energy ratios drop gradually.The increased tensile fractures and decreased shear fractures indicate that the failure mode of the unloading rock gradually changes from tensile-shear mode to tensile-split one.The fractional dimension of the rock fragments first increases and then decreases with an inflection point at 20 MPa.The distribution of SIF on the planes changes as σ2 increases,resulting in strengthening and then weakening of the rock bearing capacity.
      原文链接:
    • NETL
    • NSTL
    • 万方数据
    • 维普

    Drill bit wear monitoring and failure prediction for mining automation

    Hamed RafeziFerri Hassani
    289-296页
    查看更多>>摘要：This article introduces a novel approach for tricone bit wear condition monitoring and failure prediction for surface mining applications.A successful bit health monitoring system is essential to achieve fully autonomous blasthole drilling.In this research in-situ vibration signals were analyzed in time-frequency domain and signals trend during tricone bit life span were investigated and introduced to sup-port the development of artificial intelligence(AI)models.In addition to the signal statistical features,wavelet packet energy distribution proved to be a powerful indicator for bit wear assessment.Backpropagation artificial neural network(ANN)models were designed,trained and evaluated for bit state classification.Finally,an ANN architecture and feature vector were introduced to classify the bit condition and predict the bit failure.
      原文链接:
    • NETL
    • NSTL
    • 万方数据
    • 维普

    Compression failure conditions of concrete-granite combined body with different roughness interface

    Huan GaoYue ZhaiTienan WangYubai Li...
    297-307页
    查看更多>>摘要：Bedrock and concrete lining are typical composite structures in the engineering field and the stability of the geological body and engineering body is directly connected to the mechanical properties of the com-posite body.Under this background,the study provides the transverse isotropic equivalent model of concrete-granite double-layer composite based on the notion of strain energy equivalence.Assuming that the strength failure of concrete and granite meets the Mohr-Coulomb criterion,then the strength failure model of the combined body considering the joint roughness coefficient(JRC)is derived,and the influ-ences of JRC,the height ratio of concrete to granite,and confining pressure on the strength failure char-acteristics of the combined body are emphatically analyzed.Finally,the model applicability is illustrated by the uniaxial and triaxial compression tests on concrete monomer,granite monomer and concrete-granite composite samples(CGCSs)with different JRCs.The results revealed that the compressive strength of the composite is closer to the concrete with lower strength in the combined body under dif-ferent confining pressures.Adding interface roughness causes to raise the compressive strength of the composite due to interfacial adhesion between concrete and granite,and a slowing growth trend is observed in compressive strength as roughness.The model can provide a certain reference for the stabil-ity design and evaluation of engineering rock mass.
      原文链接:
    • NETL
    • NSTL
    • 万方数据
    • 维普

    Lateral abutment pressure distribution and evolution in wide pillars under the first mining effect

    Zhen ZhangZhen LiGang XuXiaojin Gao...
    309-322页
    查看更多>>摘要：The wide pillars are generally popular due to the high productivity and efficiency in Northwest China.The distribution of lateral abutment pressure in coal pillars is important for mining safety.To reveal the effect of the first mining on the lateral abutment pressure distribution and evolution in wide pillars,an in-situ experiment,theoretical analysis and numerical simulation were performed.First,the field monitoring of lateral abutment pressure was conducted from the perspective of time and space in the Chahasu Coal Mine,Huangling No.2 Coal Mine and Lingdong Coal Mine during the first mining.Based on the field mon-itoring stress,a theoretical model was proposed to reveal the lateral abutment pressure distribution.The methodology was demonstrated through a case study.Aiming at the distribution mechanism,a numer-ical experiment was conducted through the finite-discrete element method(FDEM).Last,field observa-tions of borehole fractures were performed to further study the damage distribution.In addition,two types of lateral abutment pressure evolution with mining advance were discussed.Suggestions on the stress monitoring layout were proposed as well.The results could provide foundations for strata control and disaster prevention in wide pillars in underground coal mines.
      原文链接:
    • NETL
    • NSTL
    • 万方数据
    • 维普

    Enhancing fly ash utilization in backfill materials treated with CO2 carbonation under ambient conditions

    Ichhuy NgoLiqiang MaJiangtao ZhaiYangyang Wang...
    323-337页
    查看更多>>摘要：The environmental concerns resulting from coal-fired power generation that produces large amounts of CO2 and fly ash are of great interest.To mitigate,this study aims to develop a novel carbonated CO2-fly ash-based backfill(CFBF)material under ambient conditions.The performance of CFBF was investigated for different fly ash-cement ratios and compared with non-CO2 reacted samples.The fresh CFBF slurry conformed to the Herschel-Bulkley model with shear thinning characteristics.After carbonation,the yield stress of the fresh slurry increased significantly by lowering fly ash ratio due to gel formation.The setting times were accelerated,resulting in approximately 40.6％of increased early strength.The final strength decreased when incorporating a lower fly ash ratio(50％and 60％),which was related to the existing heterogeneous pores caused by rapid fluid loss.The strength increased with fly ash content above 70％because additional C-S(A)-H and silica gels were characterized to precipitate on the grain surface,so the binding between particles increased.The C-S(A)-H gel was developed through the pozzolanic reac-tion,where CaCO3 was the prerequisite calcium source obtained in the CO2-fly ash reaction.Furthermore,the maximum CO2 uptake efficiency was 1.39 mg-CO2/g-CFBF.The CFBF material is feasible to co-dispose CO2 and fly ash in the mine goaf as negative carbon backfill materials,and simultaneously mitigates the strata movement and water lost in post-subsurface mining.
      原文链接:
    • NETL
    • NSTL
    • 万方数据

    Experimental and theoretical study on the dynamic effective stress of loaded gassy coal during gas release

    Bing ZhangHanpeng WangPeng WangGuofeng Yu...
    339-349页
    查看更多>>摘要：In the process of mining coalbed methane(CBM),an unsteady state often arises due to the rapid extrac-tion,release and pressure relief of CBM.In this case,the effective stress of coal changes dynamically,affecting the stability of the gassy coal seam.In this paper,gas release tests of gassy coal under conven-tional triaxial compression were performed,and the dynamic effective stress(DES)during gas release was obtained indirectly based on a constitutive equation and deformation of coal.The results show that the maximum increases in DES caused by the release of free gas and adsorbed gas under the stress of 1.1 MPa were 0.811 and 5.418 MPa,respectively,which seriously affected the stress state of the coal.During the gas release,the free gas pressure and the adsorbed gas volume were the parameters that directly affected the DES and showed a positive linear relationship with the DES with an intercept of zero.The DES of the coal sample increased exponentially with time,which was determined by the contents of free and adsorbed gas.Based on the experimental results and theoretical analysis,an effective stress model was obtained for loaded gassy coal during gas release.The results of verification indicated accu-racy greater than 99％.
      原文链接:
    • NETL
    • NSTL
    • 万方数据
    • 维普

    Algorithm for cavity flow in a new-born goaf and experimental verification

    Jian LiuQichao ZhouDong WangLijun Deng...
    351-361页
    查看更多>>摘要：Prevention and control measures of spontaneous combustion of coal and gas accumulation in a goaf require an accurate description of its gas flow state.However,the commonly used fluid dynamics in por-ous media is not suitable for the new-born goaf with fracture cavity combination,multi-scale,and large blocks.In this study,we propose a cavity flow algorithm to accurately describe the gas flow state in the new-born goaf.The genetic algorithm(GA)is used to randomly generate the binary matrix of a goaf cav-ing shape.The difference between the gas flow state calculated by the lattice Boltzmann method(LBM)and the measured data at the boundary or internal measuring points of the real goaf is taken as the GA fitness value,and the real goaf caving shape and the gas flow state are quickly addressed by GA.The experimental model of new-born goaf is established,and the laser Doppler anemometry(LDA)experi-ment is carried out.The results show that the Jaccard similarity coefficient between the reconstructed caving shape and the real caving shape is 0.7473,the mean square error between the calculated wind speed and the LDA-measured value is 0.0244,and the R2 coefficient is 0.8986,which verify the feasibility of the algorithm.
      原文链接:
    • NETL
    • NSTL
    • 万方数据
    • 维普

    Using pectin to separate talc and molybdenite through the surface modification with Cu2+:Applications and mechanism

    Changtao WangQilin ZhaiRunqing LiuMeirong Wu...
    363-377页
    查看更多>>摘要：Organic depressants have low selectivity in separating molybdenite and talc because their metal sites lack activity for organics chemisorption.In this study,surface modification by copper sulfate was used to induce the differential adsorption of pectin onto molybdenite and talc surfaces for enhanced flotation separation.Contact-angle experiments,scanning electron microscopy,adsorption measurements,time-of-flight secondary-ion mass spectrometry,and X-ray photoelectron spectroscopy analyses were con-ducted to reveal the interaction mechanism.Results illustrated that molybdenite and talc could not be separated using pectin alone,while molybdenite was selectively depressed after surface modification by copper sulfate and this effect was strengthened under alkaline conditions.Metal sites(Mg,Si and Mo)of talc and molybdenite themselves were unable to react with pectin,whereas Cu+would deposit and further function as active site for pectin chemisorption after surface modification.However,the quantity of deposited Cu sites dropped on talc surface and increased on molybdenite surface with increased pH,and the Mo atoms of molybdenite crystal were activated to take part in pectin chemisorp-tion.Therefore,more pectin was adhered on molybdenite surface,which imparted molybdenite stronger wettability.Herein,surface-modification through metal ions can enable the differential adsorption of organic depressants and enhance the flotation separation of minerals.
      原文链接:
    • NETL
    • NSTL
    • 万方数据

    Flotation separation of wolframite from calcite using a new trisiloxane surfactant as collector

    Shuyi ShuaiZhiqiang HuangVladimir E.BurovVladimir Z.Poilov...
    379-387页
    查看更多>>摘要：Since wolframite is usually associated with calcite,the separation and enrichment of wolframite by froth flotation remains a great challenge.Herein,a novel trisiloxane surfactant N-(2-aminoethyl)-3-ami nopropyltrisiloxane(AATS)was successful synthesized,which was used for the separation of wol-framite from calcite for the first time.The flotation separation performance of AATS was studied by flotation test,and its adsorption mechanism was explored based on contact angle,infrared spectrum analysis(FTIR),zeta potential and density functional theory(DFT)calculation.The results of micro-flotation test and binary mixed ore flotation test pointed that AATS had excellent selectivity and more prominent collection capacity for the flotation of wolframite when compared with industrial reagent sodium oleate(NaOL).The measurement results of contact angle proved that AATS improved the hydrophobicity of the wolframite surface.The highly selective adsorption mechanism of AATS surfac-tant on mineral surfaces were further researched and analyzed by FTIR and zeta potential.The results revealed that AATS surfactant had significant adsorption effect on wolframite,yet almost no adsorption on calcite.DFT calculation indicated that AATS produced electrostatic adsorption with wolframite sur-face through-N+H3 group.
      原文链接:
    • NETL
    • NSTL
    • 万方数据
    • 维普