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两端销接式吊索索长控制技术 被引量:3
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作者 张士轩 石艺歌 《世界桥梁》 北大核心 2021年第5期41-46,共6页
五峰山长江大桥为主跨1092 m的钢桁梁公铁两用悬索桥,主缆每个吊点设置2根两端销接式吊索,规格均为PESC5-337,全桥共计312根。针对该桥吊索索长的高精度要求,在吊索预制过程中,采用了一次无应力测量加一次恒载力测量的索长控制技术。通... 五峰山长江大桥为主跨1092 m的钢桁梁公铁两用悬索桥,主缆每个吊点设置2根两端销接式吊索,规格均为PESC5-337,全桥共计312根。针对该桥吊索索长的高精度要求,在吊索预制过程中,采用了一次无应力测量加一次恒载力测量的索长控制技术。通过制作试验索测定吊索性能参数;采用基线台座法进行无应力索长测量下料,减少索长测量及切割下料工序次数;采用测力仪间隔布置串联连接进行吊索恒载力索长测量,在采用全站仪测量得到索长的基础上,经过温度修正、垂度修正、力差弹性修正校核两端销接式吊索索长精度。按照该吊索索长控制技术,顺利完成全桥吊索的制作,吊索索长精度满足设计要求。 展开更多
关键词 悬索桥 吊索 索长控制 无应力测量 恒载力索长 基线台座法
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Constraining fast radio burst progenitors with gravitational lensing 被引量:1
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作者 LI ChunYu LI LiXin 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2014年第7期1390-1394,共5页
Fast Radio Bursts(FRBs)are new transient radio sources discovered recently.Because of the angular resolution restriction in radio surveys,no optical counter part has been identified yet so it is hard to determine the ... Fast Radio Bursts(FRBs)are new transient radio sources discovered recently.Because of the angular resolution restriction in radio surveys,no optical counter part has been identified yet so it is hard to determine the progenitor of FRBs.In this paper we propose to use radio lensing survey to constrain FRB progenitors.We show that,different types of progenitors lead to different probabilities for a FRB to be gravitationally lensed by dark matter halos in foreground galaxies,since different type progenitors result in different redshift distributions of FRBs.For example,the redshift distribution of FRBs arising from double stars shifts toward lower redshift than of the FRBs arising from single stars,because double stars and single stars have different evolution timescales.With detailed calculations,we predict that the FRB sample size for producing one lensing event varies significantly for different FRB progenitor models.We argue that this fact can be used to distinguish different FRB models and also discuss the practical possibility of using lensing observation in radio surveys to constrain FRB progenitors. 展开更多
关键词 star formation radio sources gravitational lenses and luminous arcs COSMOLOGY
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