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Deformation tests and failure process analysis of an anchorage structure

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International Journal of Mining Science and Technology 2015年第2期25卷 237-242页

作者： Zhao Tongbin yin yanchun Tan Yunliang Song Yimin State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology Shandong University of Science and Technology Faculty of Resources and Safety Engineering China University of Mining and Technology College of Architectural Engineering North China University of Technology

In order to study the failure process of an anchorage structure and the evolution law of the body＇s defor- mation field, anchor push-out tests were carried out based on digital speckle correlation methods （DSCM）. The stress distribution of the anchorage interface was investigated using the particle flow numerical simulation method. The results indicate that there are three stages in the deformation and fail- ure process of an anchorage structure： elastic bonding stage, a de-bonding stage and a failure stage. The stress distribution in the interface controls the stability of the structure. In the elastic bonding stage, the shear stress peak point of the interface is close to the loading end, and the displacement field gradually develops into a ＂V＂ shape, in the de-bonding stage, there is a shear stress plateau in the center of the anchorage section, and shear strain localization begins to form in the deformation field. In the failure stage, the bonding of the interface fails rapidly and the shear stress peak point moves to the anchorage free end. The anchorage structure moves integrally along the macro-cracl~ The de-bonding stage is a research focus in the deformation and failure process of an anchorage structure, and plays an important guiding role in roadway support design and prediction of the stability of the surrounding rock.

关键词： Anchorage structure Digital speckle correlation methods Deformation field Interface stress Failure process

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International Journal of Mining Science and Technology 2021年第3期31卷 495-505页

作者： Xuesheng Liu Shilin Song Yunliang Tan Deyuan Fan Jianguo Ning Xuebin Li yanchun yin College of Energy and Mining Engineering Shandong University of Science and TechnologyQingdao 266590China State Key Laboratory of Mining Disaster Prevention and Control Shandong University of Science and TechnologyQingdao 266590China

Large and super-large section chamber groups in coal mines are frequently affected by dynamic loads resulting from production activities such as roadway driving and *** stability of the surrounding rock is poor,and it is difficult to *** this paper,a similar simulation test was used to study the deformation and evolution laws of the surrounding rock of a triangle-shaped chamber group under different dynamic *** results showed that under dynamic loading,the vertical stress of the surrounding rock of the chamber group increased in an oscillatory *** maximum stress concentration coefficient reached *** damage degree of the roof was greater than that of the two *** deformation of the roof was approximately 1.2 times that of the two *** the chamber closer to the power source,the stress oscillation amplitude of the surrounding rock was larger,and the failure was more *** force of the anchorage structure showed a phased increasing characteristic;additionally,the force of the anchorage structure on the adjacent side of the chambers was greater than that on the other *** study reveals the deformation and failure evolution laws of the surrounding rock of large section chamber groups under dynamic loading.

关键词： Dynamic disturbance Large section chamber group Deformation and failure Similar simulation test

Generation of high-energy narrowband 2.05 μm pulses for seeding a Ho：YLF laser

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Photonics Research 2018年第1期9卷 1-5页

作者： yanchun yin xiaoming ren yang wang fengjiang zhuang jie li zenghu chang Institute for the Frontier of Attosecond Science and Technology CREOL and Department of Physics University of Central Florida Orlando Florida 32816 USA

We experimentally demonstrate efficient generation of high-energy(82 μJ) narrowband 2.05 μm pulses pumped with 1 mJ broadband Ti:sapphire laser pulses, utilizing dual-chirped optical parametric amplification(DC-OPA)in a BBO crystal. The narrowband 2.05 μm pulses will be primarily used for seeding an Ho:YLF laser, which solves the synchronization issue when Ti:sapphire and Ho:YLF lasers are needed for developing midinfrared lasers. The narrowband 2.05 μm pulse from the unique DC-OPA design can seed the Ho:YLF laser much more efficiently than the broadband 2.05 μm pulse from traditional OPA technology.

关键词：脉冲泵通讯技术发展现状技术创新

侧压力系数对煤体水力裂缝扩展规律的影响研究

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煤矿安全 2020年第11期51卷 210-215页

作者：蓝盛尹延春山东科技大学能源与矿业工程学院山东青岛266590 山东科技大学矿山灾害预防控制省部共建国家重点实验室培育基地山东青岛266590

为研究水力压裂过程中煤体水力裂缝起裂及扩展特征,采用颗粒流软件PFC2D建立煤体流固耦合模型,分析了侧压力系数对裂缝扩展及动能演化规律影响。结果表明:煤体水力压裂破坏形式为拉剪破坏,其中距离注水孔较近的裂缝主要源于张拉破坏,而... 详细信息

为研究水力压裂过程中煤体水力裂缝起裂及扩展特征,采用颗粒流软件PFC2D建立煤体流固耦合模型,分析了侧压力系数对裂缝扩展及动能演化规律影响。结果表明:煤体水力压裂破坏形式为拉剪破坏,其中距离注水孔较近的裂缝主要源于张拉破坏,而距离注水孔较远的裂缝产生较多剪切破坏;侧压力系数λ在1.6~3.4范围内,煤体的起裂压力随侧压力系数增加而减小;相同时间内水力裂缝延伸距离随侧压力系数增加而增加,当λ≥2.8,裂缝转向后沿着煤样对角方向延伸;扩展速率由快到慢,侧压力系数增大不仅促进水力裂缝的发育,还增大裂缝的扩展速率,但随着侧压力系数的提升,其对裂缝扩展速率的影响逐渐降低。

关键词：水力压裂侧压力系数裂缝扩展动能演化破坏形式

Theoretical framework for stress relief-support reinforcement cooperative control of rock bursts in deep coal mining

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Geohazard Mechanics 2024年第1期2卷 49-57页

作者： Tongbin Zhao Weiyao Guo Dongxiao Zhang Yunliang Tan yanchun yin Yan Tan Yujing Jiang Jinpeng Yao College of Energy and Mining Engineering Shandong University of Science and TechnologyQingdao266590China State Key Laboratory of Mining Disaster Prevention and Control Cofounded by Shandong Province and the Ministry of Science and Technology Shandong University of Science and TechnologyQingdao266590China Graduate School of Engineering Nagasaki UniversityNagasaki852-8521Japan

With the increasing depth of coal mining each year,rock burst has emerged as one of the most severe dynamic disasters in deep *** research status of rock burst prevention and control theory is *** on deep coal mining,the major issues encountered in researching the prevention theory of rock bursts are ***,the scientific connotation theory of stress relief-support reinforcement cooperative prevention and control of rock bursts in deep coal mines is ***,the mechanisms underlying the major research directions of the theory of stress relief-support reinforcement coordinated prevention and control and present a preliminarily theoretical framework for stress relief-support reinforcement coordinated prevention and control are *** tackle the key scientific problems in the coordinated prevention and control of rock bursts on relief and support in deep mine,the in-depth research based on the synergetic theory is *** involved exploring the principles of near-field coal mass stress relief,near-field roof andfloor stress relief,and anchor ***,the stress-energy evolution processes of the roadway near-field surrounding rock structure under various stress relief and anchor support modes be ***,a mechanical model for the optimized matching of stress relief surrounding rock and anchor support is established,with the control of the rock burst energy source at its ***,the principle of collaborative prevention and control of deep mining rock burst stress relief and support from the perspectives of structural synergy,strength synergy,and stiffness synergy is *** insight is expected to provide theoretical support for the research and development of designs and techniques for deep mining rock burst prevention and control.

关键词： Deep mining Rock burst Stress relief Support Collaborative prevention and control

高质量发展与体育产业结构:特征、内涵与对策

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南京体育学院学报 2023年第11期22卷 21-28页

作者：尹彦淳三江学院体育部江苏南京210012

体育产业的高质量发展对体育产业成为国民经济支柱性产业有着重要的指导意义,对全民健身的推广和普及有着不可替代的作用。以2016—2019年体育产业公告数据为基础,结合《国家统计年鉴》、第三次和第四次经济普查数据,通过偏离——份额... 详细信息

体育产业的高质量发展对体育产业成为国民经济支柱性产业有着重要的指导意义,对全民健身的推广和普及有着不可替代的作用。以2016—2019年体育产业公告数据为基础,结合《国家统计年鉴》、第三次和第四次经济普查数据,通过偏离——份额分析法(SSM法)对体育产业下属服务业、建筑业、制造业部门总体发展情况和结构特征进行分析,在此基础上将与体育产业相关的人口结构、消费构成、经济基础、体育系统4个维度共24项统计数据纳入体育产业灰色关联系统。SSM法对体育产业的特征研究发现:我国体育产业增长快于全国总体经济增长,体育产业下属的体育服务业、体育建筑业和体育制造业三部门综合结构存在不合理,体育建筑业出现较大偏差,体育制造业竞争力总体不强。但体育产业的发展潜力巨大,竞争优势正在不断提升。继续使用灰色关联分析对体育产业内涵研究发现:体育总产业受消费构成维度影响最大,体育制造业受人口结构维度的影响较大,体育服务业则对消费构成维度的各项指标具有较高的依赖度,体育建筑业与体育服务业之间联系紧密,对总体体育产业具备支撑作用,三部门产业相互关联,互为高质量发展助力。最后对体育产业以及下属三部门产业的高质量发展方向提出了建议。

关键词：高质量发展体育产业结构偏离—份额分析法灰色关联分析法

沈阳宝能环球金融中心C70大体积自密实混凝土关键制备技术与性能研究

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混凝土 2019年第5期 138-141页

作者：殷艳春王宁韩宇中建西部建设西南有限公司四川成都610052 辽宁中建西部建设有限公司辽宁沈阳110102

结合沈阳宝能环球金融中心C70大体积自密实混凝土施工及技术要求,进行配合比设计与性能研究。研究结果表明:I级粉煤灰减水效果最明显的取代掺量在15%~20%之间,此掺量范围内可减水约7%;利用I级粉煤灰与硅灰制备出性能优异的C70大体积自... 详细信息

结合沈阳宝能环球金融中心C70大体积自密实混凝土施工及技术要求,进行配合比设计与性能研究。研究结果表明:I级粉煤灰减水效果最明显的取代掺量在15%~20%之间,此掺量范围内可减水约7%;利用I级粉煤灰与硅灰制备出性能优异的C70大体积自密实混凝土,坍落扩展度710 mm,倒坍时间3.2 s,U型箱高度差0,利于泵送,坍落扩展度与J环扩展度之差0,离析率5.9%,其高抛免振捣性能优良;降低水泥用量,能够显著降低胶凝材料体系的水化速率与收缩,胶凝材料体系绝热最高温度仅为63.5℃,且水化速率慢,7 d收缩率为1.5×10-4,对于提升混凝土的体积稳定性是有利的,粉煤灰的微集料效应进一步提升混凝土的密实度,其抗冻性能与抗渗性能大大提高;扫描电镜(SEM)结果显示,适当加入矿物掺合料,可增加混凝土结构密实性,提高抗压与抗渗性能。

关键词： C70 自密实混凝土性能试验

水力耦合作用下裂隙岩体破裂扩展及声发射能量损伤规律

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中南大学学报（自然科学版） 2022年第6期53卷 2325-2335页

作者：陈云娟高涛高成路尹延春李艳龙山东建筑大学土木工程学院山东济南250101 山东科技大学矿山灾害预防控制重点实验室山东青岛266590 山东大学岩土与结构工程研究中心山东济南250061

裂隙岩体稳定性在很大程度上受控于非连续面的分布形态和特性,在水力耦合条件下,裂隙的分布形态对地下洞室围岩稳定性尤为关键。首先,应用RFPA计算程序分析类岩石试件不同位置裂隙岩体的破裂过程、声发射特性及能量耗散规律;其次,根据... 详细信息

裂隙岩体稳定性在很大程度上受控于非连续面的分布形态和特性,在水力耦合条件下,裂隙的分布形态对地下洞室围岩稳定性尤为关键。首先,应用RFPA计算程序分析类岩石试件不同位置裂隙岩体的破裂过程、声发射特性及能量耗散规律;其次,根据声发射自定义水力耦合条件下的岩体损伤模型;最后,对水力耦合条件下隧道裂隙围岩的损伤破坏过程进行了模拟研究。研究结果表明:受裂隙位置影响,岩体受到荷载作用时,在预制裂隙两端产生拉应力集中区,受压区分布于裂纹扩展区域,各工况裂纹扩展以张拉破坏为主,裂隙工况由中部向端部变化时,其破坏效应角β逐渐增大;孔隙水压能够促进拉应力的产生,对上部和下部裂隙工况的裂纹破坏起主导作用,对中部裂隙工况破坏具有一定辅助作用,裂隙内最大孔隙水压力随裂隙位置呈“U”形演化特征;孔隙水压力的初始加载值设置越大,各工况破坏时的峰值强度和最大水压力越低;预制裂隙形成的主破裂路径长度与声发射数目和能量累积能力呈正比关系,损伤变量指标随受载过程呈“稳增长—剧增长—稳增长”变化趋势;当裂隙处于隧道右上部时,对围岩稳定性影响最显著且围岩损伤具有滞后性。

关键词：水力耦合岩体破裂裂纹扩展声发射能量损伤

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基于熵值法的动商评价体系研究

体育科技文献通报 2022年第4期30卷 231-233页

作者：尹彦淳三江学院体育部江苏南京210012

本文基于动商内涵丰富的特点构建了一套动商熵(Motor Quotient Entropy, MQE)评价体系,一定程度改善了现有动商评价体系门类繁多、数据收集繁琐、评价主观性强的问题。通过收集整理高校15394名学生《国家学生体质健康标准》九项测试数据... 详细信息

本文基于动商内涵丰富的特点构建了一套动商熵(Motor Quotient Entropy, MQE)评价体系,一定程度改善了现有动商评价体系门类繁多、数据收集繁琐、评价主观性强的问题。通过收集整理高校15394名学生《国家学生体质健康标准》九项测试数据,并通过整合处理最终得到七个动商熵权重项目,最终运用熵值法,通过加权计算得到每个学生的动商熵数据。通过对整体样本的对比分析,了解该高校学生的整体动商情况,并能直观分析个体存在的动商问题。该方法具有简单高效、数据易得、对比方便等特点,为动商概念体系的普及、动商测评体系覆盖面的扩大、全民动商提高路径的探究提供理论依据。

关键词：动商熵值法测评体系学生

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