共查询到20条相似文献,搜索用时 15 毫秒
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针对电磁超声信号信噪比低、回波特征不明显的问题,本文对磁致伸缩扭转导波特性进行了分析,扭转导波非频散适合信号处理,且在传播过程中能量衰减较小。利用ANSYS有限元仿真软件分析了扭转导播在纤维增强塑料(FRP)锚杆内的位移、功率流特性;搭建了物理实验平台,在FRP锚杆内激励和接收磁致伸缩扭转导波信号,对采集到的回波信号进行CEEMD-LMS算法滤波;实验数据验证了数值分析结果的有效性。结果表明:磁致伸缩扭转导波在FRP锚杆内的传播功率趋向于表面,适用于FRP锚杆表面缺陷检测;经CEEMD-LMS滤波算法处理后的磁致伸缩导波信号信噪比得到提升;磁致伸缩扭转导波技术可对有周向缺陷的FRP锚杆长度、缺陷位置进行识别。 相似文献
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The new structure of fibre glass reinforced plastics bolt 总被引:4,自引:0,他引:4
The develop actuality and direction of FRP (fibre glass reinforced plastics) bolt in the world are analyzed. The new type structure of FRP bolt was designed. Trial data indicate that, all kinds of capability target of this FRP bolt all achieve and exceed the country stand-ard, substitute present metal bolt, wood bolt and bamboo bolt and other side bolt, it can gain magnitude technology and economy benefit. FRP bolt mechanization product line produce ef-ficiency is high, its throughput a day are 750 base, this can meet demand of hit-small mining company. 相似文献
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基于固定岩梁和顶板岩层形变压力的假设,研究认为巷道顶板岩层的变形与破坏是在地层压力作用下,从顶板表面开始,由下而上、逐层向上发展的,直至到达可以承载地层压力而不被破坏的顶板岩层。据此研究提出了层状顶板巷道锚索(锚杆)支护载荷的计算方法,为煤巷锚索(锚杆)支护强度设计提供了依据。 相似文献
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针对立井井筒装备腐蚀严重的现状,提出了一种新型的玻璃钢复合材料罐道,该罐道用型钢作钢芯,在钢芯外表面用模压一次成型的方法敷上一层玻璃钢,并对这种罐道玻璃钢与钢材层合面上的抗剪性能进行了试验研究。试验与分析表明,复合材料罐道层合面抗剪性能良好,不会因层合面的抗剪能力不足而使两种材料的性能发挥受到限制。 相似文献
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《中国稀土信息》2012,(9):1-3
Ⅳ Market analysis of RE-based La series optical glass 1.RE production and market status Huge RE reserve has always been regarded as one of the advantages for China’s rare earths application in high tech fields.However,in the recent decade,the problems of disordered mining and illegal export were very severe in China.Statistics show that,at the expense of low price,low level of resource utilization,serious damage to the 相似文献
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通过对比弹性设计方法和塑性设计方法,探讨塑性设计法在连续梁(板)桥中的工程应用,说明采用塑性内力重分布理论设计能更准确地反映超静定结构在进入塑性阶段后的受力状况. 相似文献
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Industrial scale Horomill® and hybrid HPGR/two-compartment ball mill applications at puzzolanic portland cement production were presented with emphasis on the general operational characteristics of the circuit configurations, size reduction and energy efficiencies of the Horomill® and two-compartment ball mill grinding conditions. Horomill® circuit configuration indicated to have advantages in terms of production of high strength cement as compared to Hybrid HPGR/two-compartment ball milling, depending on the classification performance of the separators influencing the circuit performance. 相似文献
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随着井工煤矿高强度开采及开采深度的增加,巷道围岩控制难度逐步增大,造成巷道支护困难,损坏、修复率加剧.在煤矿事故中,巷道顶板事故频发.因此,安全、可靠、高效的巷道支护技术是实现矿井安全高效生产的必要条件.通过创新改进现有锚杆支护系统,提高锚杆(索)杆体预应力、预紧力,让锚杆(索)杆体强度、锚固力、预紧力科学合理匹配,实... 相似文献
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C11A7·CaF2和C4A3(S)矿相煤矸石快硬喷射水泥的试验研究 总被引:1,自引:0,他引:1
利用工业废渣煤矸石烧制矿山及地下工程用喷射水泥,该水泥含快硬矿相C11A7*CaF2,C4A3S和C3S,C2S.C11A7*CaF2和C4A3S水化产物提供早期强度,C3S和C2S水化产物保证中后期强度.该水泥初凝5 min,终凝10 min,4 h后强度为7 MPa;中后期强度稳定增长,凝结时间和强度满足喷射要求. 相似文献