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钢筋计与锚杆应力计测值超极限范围的分析
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作者 廖占勇 《水电自动化与大坝监测》 2014年第3期25-29,共5页
钢筋计与锚杆应力计是地下洞室与边坡支护的常用仪器,主要用于测量地下洞室支护的钢筋应力和锚杆的锚固力与拉拔力。工程使用中发现有部分钢筋计与锚杆应力计的测值已经超出钢筋和锚杆本身的极限强度,但结构物并没有发现损坏。找出这些... 钢筋计与锚杆应力计是地下洞室与边坡支护的常用仪器,主要用于测量地下洞室支护的钢筋应力和锚杆的锚固力与拉拔力。工程使用中发现有部分钢筋计与锚杆应力计的测值已经超出钢筋和锚杆本身的极限强度,但结构物并没有发现损坏。找出这些超出钢筋极限强度测值产生的原因,及判断这些测值是否可信是一个急需解决的问题。通过分析,得到仪器受侧向合力作用弯曲变形是产生这一现象的原因,并通过实验进行了验证。 展开更多
关键词 钢筋计 锚杆应力计 极限范围
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Suitable layout of gate roads related to slice mining in an ultra-thick unstable coal seam 被引量:2
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作者 Fan Gangwei Zhang Dongsheng Zhou Lei 《Mining Science and Technology》 EI CAS 2011年第4期563-566,共4页
We determi:ned a suitable gate road layout in slice mining in an ultra-thick unstable coal seam, using theoretical anallysis and numerical calculations. Based on plasticity theory in terms of limiting equilibrium, th... We determi:ned a suitable gate road layout in slice mining in an ultra-thick unstable coal seam, using theoretical anallysis and numerical calculations. Based on plasticity theory in terms of limiting equilibrium, the width of chain pillar in the upper slice was calculated to be 18 m. The stress distribution in the chain pillar after the upper slice was mined out was described with numerical simulation. The extent of the effect of stress on the upper chain pillar on the lower solid coal was obtained on the basis of an elastic solution of a distributed force loaded on a half-plane. Three layout designs for lower gate roads were pro- posed and a stability factor was introduced to analyze the stability of the lower pillar with numerical calculation. Gate road translation was determined as the most suitable layout method, which maximizes the extraction rate on the basis of the pillar stability. 展开更多
关键词 Ultra-thick coal seam Slice mining Gate road Coal pillar Stability factor
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国外道路几何设计中纵坡超标设计分析 被引量:1
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作者 吕高虎 周群 《公路》 北大核心 2015年第7期53-57,共5页
介绍国外道路设计中特殊条件下,纵坡设计时需采用超极限纵坡值的情况。对道路通行能力、上下坡安全性进行论证,提出纵坡超标设计时的解决措施,可供国外道路纵断面设计时借鉴。
关键词 国外道路 长大纵坡 超极限值
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