Results 61 to 70 of about 745 (139)
Calculation of slope stability of fault-containing slopes under the action of cyclic blast vibration [PDF]
In order to accurately quantify and predict the evolution of slope stability of fault-containing slopes under the long-term effect of blasting vibration, and to realize the safe, efficient and sustainable mining of open-pit mines. Taking an open-pit mine
Dong WANG +3 more
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Research on intelligent design of coal mine roadway support scheme [PDF]
Currently, the design of coal mine roadway support schemes is still mainly based on manual design, engineering analogy, and FLAC model simulation, which has problems such as strong subjectivity, low universality, and insufficient utilization of coal mine
CHEN Wanhui +8 more
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, 2019 为研究干湿循环对花岗岩残积土抗剪强度特性和抗剪强度参数的影响,分析花岗岩残积土边坡的稳定性,改进了常规的单元试验方法.以整个花岗岩残积土边坡为试验对象进行干湿循环模拟,在每次循环后直接在边坡坡面上切取花岗岩残积土试样进行直剪试验.在此基础上,利用有限元软件ABAQUS对一实际边坡进行了干湿循环的数值模拟,在每次循环模拟前对上一次模拟结果进行分析,将等效塑性应变较大区域的土体强度进行适当折减,分析每次循环后花岗岩残积土边坡的应力应变、稳定性以及塑性变形.试验结果表明:花岗岩残积土的抗剪强度随干湿循环次数 ...
于佳静, 张波, 王晖, 陈东霞
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Shuitu Baochi Xuebao, 2019 选择三峡库区典型紫色土坡耕地埂坎为研究对象，通过室内三轴不固结不排水试验（UU）研究加筋对埂坎土壤抗剪特征的影响。结果表明：（1）3种试验材料加筋土均表现出土壤黏聚力随着加筋量的增加先增大后减小，埂坎土壤黏聚力大小表现为：c麦壳 > c竹丝 > c稻秆 > c素土。埂坎土壤黏聚力最大时，麦壳、竹丝和稻秆的加筋量分别为0.8%，0.5%和0.3%。加筋材料对土壤内摩擦角的影响不明显。（2）3种加筋材料均能提升土壤抗剪强度。土壤极限主应力差随着加筋量的增加先增大后减小，麦壳 ...
刘春红, 韦杰, 史炳林, 李进林
doaj
Shuitu Baochi Xuebao, 2019 为探索钠盐含量变化对海涂粉砂土工程边坡稳定性的影响，以界限含水率试验和抗剪强度测定试验为基础，分析Na+含量对粉砂土界限含水率和抗剪强度等土力学参数的响应规律，并结合无限边坡安全系数计算，明确不同饱和度条件下土壤Na+含量变化对边坡稳定性的影响。结果表明：随着Na+含量增加，土样塑限呈缓慢增大趋势，而液限呈减小的变化规律。平均黏聚力和平均内摩擦角均随Na+含量增加而减小。对相同质地土壤，当饱和度不变时，边坡安全系数FS随Na+含量增加而减小；当Na+含量不变时，土壤饱和度越大，安全系数FS越小 ...
郑一鹏, 佘冬立, 王洪德
doaj
Failure mechanism of tip-to-face roof based on energy method and experimental investigation of support-strata interaction [PDF]
In order to study the stability and influencing factors of the end face roof of the full-mechanized mining face, a mechanical model of tip-to-face roof stability was developed in this study with a combination of the energy method and the “roof-support ...
Dezhong KONG +5 more
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Three-dimensional pressure-relief prevention and control technology and its application in deep gob-side entry [PDF]
In response to the challenges posed by significant deformation and maintenance difficulties in the surrounding rock of deep gob-side entries. This study focuses on the 7312 head entry as the research background.
Changqing LI +6 more
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Journal of China and International Relations, 2019 当前中美经贸关系步入摩擦多发期，经贸关系已从中美关系的“压舱石”蜕变为“导火索”。美国政府频繁发起对华贸易争端，使用各种贸易救济工具为国内敏感产业提供保护，采取单边贸易措施提高在中美贸易谈判中的要价。面临美国的贸易单边主义政策和全球经济持续性放缓的趋势，如何提升中国在国际贸易投资领域的话语权和规则制定权？如何增强中国和广大发展中国家参与全球价值链分工的能力？本文从全球价值链重构视角，基于中国与立陶宛经贸投资合作的经验与证据，探析我国提升参与全球经济治理能力的产业政策选择与微观基础 ...
Chen Bin, Cheng Yonglin, Li Rujian
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Gaoya dianqi, 2019 针对西北电网某变电站高压断路器液压操作机构频繁打压故障,通过解体分析,逐步排查各部件,发现是由于一级阀密封圈损坏,导致控制阀渗漏油;油压开关存在内渗漏,油箱防震容器损坏,从而导致油泵频繁启动。通过分析部件动作过程及生产工艺,发现控制阀阀座?6小孔与倒角不同轴造成两侧受力不均,密封圈局部发生变形;储能活塞与活塞缸的接触面过于粗糙,摩擦产生的杂质混入液压油;活塞、导向杆以及弹簧座的配合尺寸研磨不当;在装配过程中防震容器的阀口或钢珠损坏;这4点都是导致液压油渗漏的原因。此外 ...
马佳豪 +5 more
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Research on the influence of seepage on the mechanical behavior and slope stability of granite residual soil [PDF]
, 2017 花岗岩残积土在我国东南沿海地区广泛分布，是很多工程构筑物的组成材料、地基或地层环境介质。渗流会对土体产生力学、物理和化学方面的作用，从而导致土体力学特性变化，影响边坡稳定性。因此研究渗流对花岗岩残积土的力学特性及边坡稳定性影响具有重要的理论和现实意义。 本文在总结分析土体力学特性、渗透特性和渗流对土体力学特性及边坡稳定性影响研究发展概况的基础上，利用土工基础试验仪器和三轴渗流剪切试验仪，借助有限元分析软件，进行了以下几方面的工作： (1)测试分析了花岗岩残积土试样含水率、比重、颗粒组成 ...
李祥华
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