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《铁道标准设计通讯》2017,(3):124-128
建立盾构隧道三维数值模型,在管片内侧施加特定速度和角度的列车脱轨撞击荷载,获取与被撞击块相连6颗螺栓所在位置的接头错动及张开量时程曲线。通过对比分析在撞击过程中不同位置接头的错动和张开量变化趋势以及出现的最大张开、错动量,揭示在列车小角度撞击作用下盾构隧道管片接头张开和错动特性。结果表明:在速度200 km/h列车斜向12.5°撞击作用下,各螺栓位置的管片接头均出现不同程度的张开和错动,在撞击过程中各位置接头出现的最大错动量均远远超过实际工程中的限值;相对于管片接头的错动,撞击作用所造成的各位置接头平均张开量相对较小,某些位置接头在整个撞击过程中始终未发生张开。研究所得结论对盾构隧道的结构防撞和防水设计具有一定的参考价值。 相似文献
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何惠湘 《南通航运职业技术学院学报》2006,5(4):114-116
文章通过分析目前高等职业教育的发展现状,提出了高等职业院校只有正确定位,扬长避短,以培养适合社会需求的高技能应用型人才为目标,突出办学特色,打造品牌,与其他院校错位竞争,才能提高就业率。 相似文献
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Naoki Osawa Yasumitsu Tomita Kiyoshi Hashimoto 《Journal of Marine Science and Technology》2003,7(4):189-204
In order to accumulate knowledge about how material compositions and manufacturing methods affect fatigue strength, this
paper investigates the relationship between the swiftness of the changes in the macroscopic indices of the crack initiation
process and the hardening properties of a material. This is done by calculating the cyclic deformation behavior of a f.c.c.
single crystal. The relationship between the swiftness of the changes and the crystal geometries is also examined by calculating
the deformation behavior of a f.c.c. crystal with a high Schmid factor buried in a large crystal with a low Schmid factor.
In addition, a multiscale hardening rule based on forest theory is developed in order to examine the microscopic mechanisms
of fatigue slip band (persistent slip bands, PSBs) formation. The validity of the theories presented is examined by comparing
the changing nature of the measured and calculated hysteresis loop shapes of f.c.c. single crystals. Inhomogenous slip deformation
through the crystal is also investigated, and inferences are then drawn about the microscopic mechanisms of cyclic hardening
and PSB formation.
Received: August 5, 2002 / Accepted: December 18, 2002
Address correspondence to: N. Osawa (osawa@naoe.eng.osaka-u.ac.jp)
Updated from the Japanese original, which won the 2002 SNAJ prize (J Soc Nav Archit Jpn 1998;184:351–363, 1999;185:283–292
and 186:535–544, 2001;190:539–551) 相似文献
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