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Damage evolution of rock-encased-backfill structure under stepwise cyclic triaxial loading

Journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 597-615页

作者： Xin Yu yuye tan Weidong Song John Kemeny Shengwen Qi Bowen Zheng Songfeng Guo Key Laboratory of Shale Gas and Geoengineering Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100089China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing100089China University of Chinese Academy of Sciences Beijing100049China School of Civil and Resources Engineering University of Science and Technology BeijingBeijing100083China Key Laboratory of High-Efficient Mining and Safety of Metal Mines(Ministry of Education of China) University of Science and Technology BeijingBeijing100083China Department of Mining and Geological Engineering University of ArizonaTucsonAZ86721USA

Rock-encased-backfill(RB)structures are common in underground mining,for example in the cut-andfill and stoping methods.To understand the effects of cyclic excavation and blasting activities on the damage of these RB structures,a series of triaxial stepwise-increasing-amplitude cyclic loading experiments was conducted with cylindrical RB specimens(rock on outside,backfill on inside)with different volume fractions of rock(VF=0.48,0.61,0.73,and 0.84),confining pressures(0,6,9,and 12 MPa),and cyclic loading rates(200,300,400,and 500 N/s).The damage evolution and meso-crack formation during the cyclic tests were analyzed with results from stress-strain hysteresis loops,acoustic emission events,and post-failure X-ray 3D fracture morphology.The results showed significant differences between cyclic and monotonic loadings of RB specimens,particularly with regard to the generation of shear microcracks,the development of stress memory and strain hardening,and the contact forces and associated friction that develops along the rock-backfill interface.One important finding is that as a function of the number of cycles,the elastic strain increases linearly and the dissipated energy increases exponentially.Also,compared with monotonic loading,the cyclic strain hardening characteristics are more sensitive to rising confining pressures during the initial compaction stage.Another finding is that compared with monotonic loading,more shear microcracks are generated during every reloading stage,but these microcracks tend to be dispersed and lessen the likelihood of large shear fracture formation.The transition from elastic to plastic behavior varies depending on the parameters of each test(confinement,volume fraction,and cyclic rate),and an interesting finding was that the transformation to plastic behavior is significantly lower under the conditions of 0.73 rock volume fraction,400 N/s cyclic loading rate,and 9 MPa confinement.All the findings have important practical implications on the ability of backfill to support underground ex

关键词： Rock and backfill Triaxial cyclic loading Volume fraction Damage evolution 3D visualization

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基于G1法和云化物元模型的充填体稳定性评价

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矿业研究与开发 2024年第1期44卷 13-18页

作者：黄旭叶聪林陈家钊谭玉叶北京科技大学土木与资源学院北京100083 武钢资源集团大冶铁矿有限公司湖北黄石市435006 金属矿山高效开采与安全教育部重点实验室北京100083

充填体是矿山充填开采的关键采场结构,其稳定性评判对矿山生产安全具有重要意义。针对目前充填体稳定性评价方法存在的模糊性和随机性的特点,提出了充填体稳定性综合评价方法。采用序关系分析法(G1法)和云化物元模型构建了充填体稳定性... 详细信息

充填体是矿山充填开采的关键采场结构,其稳定性评判对矿山生产安全具有重要意义。针对目前充填体稳定性评价方法存在的模糊性和随机性的特点,提出了充填体稳定性综合评价方法。采用序关系分析法(G1法)和云化物元模型构建了充填体稳定性综合评价模型,以大冶铁矿某充填体为工程背景,采用G1法确定指标权重,利用MATLAB计算单指标的云关联度及综合评价向量,由最大隶属度原则确定大冶铁矿充填体的稳定性等级。研究结果表明:采用充填体稳定性评价方法评价的充填体稳定性等级与实际情况相符,可为深部金属矿山充填体稳定性评价提供新思路及新方法。

关键词：充填体稳定性 G1法云化物元模型

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基于ShapeMetrix 3D及修正BQ分级法的节理岩体稳定性分级

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化工矿物与加工 2024年第6期53卷 37-44页

作者：朱丰浩叶聪林谭玉叶楚立申北京科技大学土木与资源工程学院武钢资源集团大冶铁矿有限公司

岩体稳定性分级是反映岩体完整性、判断岩体质量好坏、确保矿山开采安全的重要工作。为了准确高效地获得岩体节理产状信息，采用非接触式测量法调查岩体结构面。以大冶铁矿为工程背景，利用ShapeMetrix 3D系统对该矿现场19处节理裂隙进... 详细信息

岩体稳定性分级是反映岩体完整性、判断岩体质量好坏、确保矿山开采安全的重要工作。为了准确高效地获得岩体节理产状信息，采用非接触式测量法调查岩体结构面。以大冶铁矿为工程背景，利用ShapeMetrix 3D系统对该矿现场19处节理裂隙进行了精确扫描和测量，并对节理裂隙的几何参数进行了统计分析，得到了岩体产状信息。利用测量数据，基于修正的BQ分级法对该矿岩体进行分级，并将此分级结果与Q分级法和RMR分级法的分级结果进行对比，结果表明：由3种分级方法得到的岩体质量等级基本一致，岩体稳定性基本为Ⅱ级，个别位置为Ⅲ级，稳定性较好。

关键词：节理岩体稳定性分级 ShapeMetrix 3D BQ分级法非接触式测量法岩体质量

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激发药剂在矿渣基胶结材料中速凝早强机理试验研究

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黄金 2024年第5期45卷 1-4页

作者：王丽媛童川谭玉叶李伟明烟台黄金职业学院环境与材料工程系北京科技大学土木与资源工程学院山东黄金矿业(莱州)有限公司焦家金矿

以尾砂、矿渣基胶结材料为原材料,研究水玻璃、NaOH、Na_(2)SO_(4)、Al_(2)(SO_(4))_(3) 4种无机盐激发药剂在不同掺量下的速凝早强效果,并解释其早强机理。研究发现:4种激发药剂在一定的添加范围内,充填体试块的抗压强度随龄期的增长... 详细信息

以尾砂、矿渣基胶结材料为原材料,研究水玻璃、NaOH、Na_(2)SO_(4)、Al_(2)(SO_(4))_(3) 4种无机盐激发药剂在不同掺量下的速凝早强效果,并解释其早强机理。研究发现:4种激发药剂在一定的添加范围内,充填体试块的抗压强度随龄期的增长而增大。掺量0.5%的NaOH早强效果最好,掺量1.0%的Na_(2)SO_(4)效果次之,掺量0.5%的Al_(2)(SO_(4))_(3)对后期强度增长作用最明显,水玻璃效果最差。同时考虑到实用性、经济性,复合使用Na_(2)SO_(4)和Al_(2)(SO_(4))_(3)添加到尾砂胶结充填体试块中,综合性能较好。研究结果可有效提高充填体早期强度,为矿山进行充填体结构及强度优化设计提供科学参考依据。

关键词：激发药剂胶结料矿渣早期强度速凝充填体

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Criterion of local energy release rate of gob instability in deep mines considering unloading stress path

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International Journal of Mining Science and Technology 2017年第6期27卷 1011-1017页

作者： Fu Jianxin Song Weidong tan yuye Civil and Resources Engineering School University of Science and Technology Beijing Beijing 100083 China State Key Laboratory of High-Efficient Mining and Safety of Metal Mines Ministry of Education Beijing 100083 China

The stress path characteristics of surrounding rock in the formation of gob were analyzed and the unloading was solved. Taking Chengchao Iron Mine as the engineering background, the model for analyzing the instability of deep gob was established based on the mechanism of stress relief in deep mining.The energy evolution law was analyzed by introducing the local energy release rate index(LERR), and the energy criterion of the instability of surrounding rock was established based on the cusp catastrophe theory. The results show that the evolution equation of the local energy release of the surrounding rock is a quartic function with one unknown and the release rate increases gradually during the mining process.The calculation results show that the gob is stable. The LERR per unit volume of the bottom structure is relatively smaller which means that the stability is better. The LERR distribution showed that there was main energy release in the horizontal direction and energy concentration in the vertical direction which meets the characteristics of deep mining. In summary, this model could effectively calculate the stability of surrounding rock in the formation of gob. The LERR could reflect the dynamic process of energy release,transfer and dissipation and that provided an important reference for the study of the stability of deep mined out area.

关键词： Deep mine Gob Unloading Local energy release rate Cusp catastrophe

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Mechanical properties and failure modes of stratified backfill under triaxial cyclic loading and unloading

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International Journal of Mining Science and Technology 2019年第5期29卷 809-814页

作者： Wang Jie Song Weidong Cao Shuai tan yuye School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China State Key Laboratory of High-Efficient Mining and Safety of Metal Mines of Ministry of Education Beijing 100083China

Multiple filling of gobs will lead to a layered structure of the backfill.To explore the influence of layering structure on the mechanical properties and failure modes of backfill,different backfill specimens were prepared with a cement/sand ratio of 1:4,a slurry concentration of 75%,and backfilling times of 1,2,3 and 4,separately.Triaxial cyclic loading and unloading experiments were carried out.The results show that with an increase in backfilling time,the peak strength of backfill decreases as a polynomial function and the peak strain increases as an exponential function.The cyclic load enhances the linear characteristic of backfill deformation.The loading and unloading deformation moduli have a linear negative correlation with the backfilling time.The unloading deformation modulus is always slightly higher than the loading deformation modulus.The failure modes of stratified backfill are mainly characterized by conjugate shear failure at the upper layer and tensile failure across the layer plane,and there is usually no damage in the lower layer away from the loading area.

关键词： Stratified backfill Triaxial cyclic loading and unloading Mechanical properties Failure modes Deformation modulus

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Explosion resistance performance of reinforced concrete box girder coated with polyurea:Model test and numerical simulation

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Defence Technology（防务技术） 2024年第3期33卷 1-18页

作者： Guangpan Zhou Rong Wang Mingyang Wang Jianguo Ding yuye Zhang School of Science Nanjing University of Science and TechnologyNanjing 210094JiangsuChina School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094JiangsuChina State Key Laboratory of Explosion and Impact and Disaster Prevention and Mitigation Army Engineering University of PLANanjing 210007JiangsuChina

To study the anti-explosion protection effect of polyurea coating on reinforced concrete box girder,two segmental girder specimens were made at a scale of 1:3,numbered as G(without polyurea coating)and PCG(with polyurea coating).The failure characteristics and dynamic responses of the specimens were compared through conducting explosion tests.The reliability of the numerical simulation using LS-DYNA software was verified by the test results.The effects of different scaled distances,reinforcement ratios,concrete strengths,coating thicknesses and ranges of polyurea were studied.The results show that the polyurea coating can effectively enhance the anti-explosion performance of the girder.The top plate of middle chamber in specimen G forms an elliptical penetrating hole,while that in specimen PCG only shows a very slight local dent.The peak vertical displacement and residual displacement of PCG decrease by 74.8% and 73.7%,respectively,compared with those of specimen G.For the TNT explosion with small equivalent,the polyurea coating has a more significant protective effect on reducing the size of fracture.With the increase of TNT equivalent,the protective effect of polyurea on reducing girder displacement becomes more significant.The optimal reinforcement ratio,concrete strength,thickness and range of polyurea coating were also drawn.

关键词： Explosive load Explosion resistance performance Model test Polyurea Concrete box girder Numerical simulation

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LaMnO_(3)/Co_(3)O_(4) nanocomposite for enhanced triethylamine sensing properties

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Journal of Rare Earths 2024年第4期42卷 733-742页

作者： Jian Zhang Yanping Chen Ling Li Xue Chen Wenya An Xiujuan Qian yuye Tao School of Science Shandong Jianzhu UniversityJinan250100China

LaMnO_(3) modified Co_(3)O_(4) nanocomposites were prepared by simple hydrothermal method co mbined with sol-gel method.The gas sensitivity properties of pure Co_(3)O_(4) and LaMnO_(3)/Co_(3)O_(4) with different composite proportions are compared.It is found that 0.6-LMO/Co_(3)O_(4) sensor has higher sensitivity to triethylamine(TEA)than pure Co_(3)O_(4) sensor,which is improved by 9.27 times.And the working temperature is reduced from 150 to 130℃.Besides,it has excellent gas selectivity and repeatability.The improvement of the gas sensitivity of LaMnO_(3)/Co_(3)O_(4) sensor may be due to the fact that LaMnO_(3) is an effective catalyst,and the catalytic performance perhaps is beneficial to improving the sensing performance.In addition,the formation of p-p heterojunctions may be the key factor to improve the gas sensing performance.This work provides a new Co_(3)O_(4)-based gas sensing material for the detection of TEA.

关键词： Gas sensing Co_(3)O_(4) LaMnO_(3) Triethylamine Rareearths

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充填体包裹岩石组合强度与破坏机理研究

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中国矿业大学学报 2023年第1期52卷 30-42页

作者：余昕谭玉叶宋卫东汪杰北京科技大学土木与资源工程学院北京100083 北京科技大学金属矿山高效开采与安全教育部重点实验室北京100083 中国科学院地质与地球物理研究所中国科学院页岩气与地质工程重点实验室北京100029

充填体与岩石的组合力学特性及破坏机理是深部充填法开采中的重要研究方向,对于保障地下采场安全、维护地下采场结构的永久稳固至关重要.文章针对充填体包裹岩石(BR)这一组合结构试件开展了单轴、三轴力学试验研究,分析了应力-应变曲线... 详细信息

充填体与岩石的组合力学特性及破坏机理是深部充填法开采中的重要研究方向,对于保障地下采场安全、维护地下采场结构的永久稳固至关重要.文章针对充填体包裹岩石(BR)这一组合结构试件开展了单轴、三轴力学试验研究,分析了应力-应变曲线、峰值强度、破裂模式和等效力学特性,探索了体积分数及围压对组合结构承压特性及破坏机制的影响.结果表明:充填体能够抑制尺寸效应对岩石破裂模式产生的影响;BR试件的三轴全应力-应变曲线呈现出多峰值、阶梯式下降现象,兼具脆性和延性破坏特征;随着围压的增加,BR试件破裂模式以剪切破坏为主,趋于集中在上端部;结构面抑制了BR试件的侧向形变.基于试验结果和连续介质理论,从力学角度分析了BR组合结构的三向受力机理,构建了组合破坏强度模型.研究结论对于补充充填体与岩石相互作用理论研究和优化地下充填采场结构稳定性控制具有重要的科学意义.

关键词：充填体包裹岩石三轴压缩力学特性破裂模式接触面

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Electroacupuncture targeting the immune system to alleviate sepsis

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Acupuncture and Herbal Medicine 2024年第1期4卷 56-67页

作者： Mengyue Fang yuye Lan Man Li Chennan Li Bin Xu Yan Ma Sulukkana Noiprasert Xianghong Jing Lingling Yu Tongji Hospital Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina School of Basic Medicine Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina Key Laboratory of Integrated Acupuncture and Medicine Research of Ministry of Education Nanjing University of Chinese MedicineNanjingChina Wuhan No.1 Hospital Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina School of Integrative Medicine Mae Fah Luang UniversityChiangraiThailand Institute of Acupuncture and Moxibustion China Academy of Chinese Medical SciencesBeijingChina Institute of Integrated Traditional Chinese and Western Medicine Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina

Sepsis is a life-threatening inflammatory syndrome with high morbidity and mortality rates.However,options for sepsis are still limited to general treatment in intensive care units(ICUs),and effective therapies that improve sepsis survival are required.Immune disturbances play a vital role in the pathology of sepsis and are associated with protracted inflammation,susceptibility to infections,and death.Therefore,many investigators have focused on the potential benefits of immunomodulation therapy for sepsis.Electroacupuncture(EA)has been practiced in clinics for many years and has shown advantages in treating infectious diseases.Over the last few decades,our understanding of the efficacy and mechanisms of EA in sepsis has undergone considerable developments.We searched the literature regarding“CNKI,Wan Fang Data,VIP Database,PubMed,and Ingenta Connect”from 2010 to 2023,using the keywords“sepsis”“septic”and“electroacupuncture”and 336 sources were searched.Finally,we included 82 studies that targeted the immune system to determine EA’s anti-inflammatory and immunomodulatory effects on sepsis.In this review,we found that EA has clinical benefits in relieving septic inflammation,improving immune function,and attenuating related multi-organ injury through several mechanisms,such as activation of the cholinergic anti-inflammatory pathway(CAP),vagaladrenal axis,inhibition of the nuclear factor Kappa-B(NF-κB)signaling pathway,signal transducers and activators of transcription(STAT)signaling pathway,and improvement of immune cell function.Therefore,EA may be a promising complementary therapy for sepsis treatment.We also expect these data will contribute to further studies on EA in sepsis.

关键词： Cholinergic anti-inflammatory pathway Electroacupuncture Nuclear factor Kappa-B Sepsis Signal transducers and activators of transcription Vagal-adrenal axis

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