High-speed Railway最新文献_第7页

Improving rail vehicle dynamic performance with active suspension 利用主动悬架改善轨道车辆动力性能

High-speed Railway Pub Date : 2023-03-01 DOI: 10.1016/j.hspr.2022.12.002

Sebastian Stichel, Rickard Persson, Rocco Giossi

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引用次数: 0

A method for calculating strand tension in the anchor span of a suspension bridge considering the rotation of a splay saddle 一种考虑鞍座旋转的悬索桥锚跨张力计算方法

High-speed Railway Pub Date : 2023-03-01 DOI: 10.1016/j.hspr.2022.11.005

Xuejin Huo , Jia Chen , Dongxu Wang , Li Zhu

{"title":"A method for calculating strand tension in the anchor span of a suspension bridge considering the rotation of a splay saddle","authors":"Xuejin Huo , Jia Chen , Dongxu Wang , Li Zhu","doi":"10.1016/j.hspr.2022.11.005","DOIUrl":"https://doi.org/10.1016/j.hspr.2022.11.005","url":null,"abstract":"<div><p>This paper reports a method for strand tension in anchor spans considering rotation. A kind of co-moved coordinate system, a saddle local coordinate system, was set up. This system implemented the rotation of the splay saddle through the rotation of the coordinate system, and all calculations proceeded in this coordinate system. Considering the rotation of the anchoring surface by the rotation of the local coordinate system of the anchoring surface, the anchorage point coordinates of strands were transformed to the local saddle coordinate system. There was a two-layer iteration adopted in the calculation. In the inner iteration, the cable force at the end of the vertical bend was taken as the variable, and the ordinate of the anchorage point was taken as the target value. In the outer iteration, the vertical tangential angle at the end of the vertical bend was taken as the variable, and the ordinate of the anchorage point was taken as the target value. The method carried out the rotation of the splay saddle and anchor surface and was simple, convenient and without approximation. The effect of rotation was considered precisely; it showed stability during the process of two-layer iteration, powerful adaptation and higher efficiency and had been successfully applied in the construction control of the Wufengshan Yangtze River Bridge, the world's first kilometer-level combined highway and railway suspension bridge.</p></div>","PeriodicalId":100607,"journal":{"name":"High-speed Railway","volume":"1 1","pages":"Pages 56-62"},"PeriodicalIF":0.0,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49876336","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Behaviour of non-ballast pre-stressed and precast track structures in high speed railway based on multiscale finite element model 基于多尺度有限元模型的高速铁路无砟预应力和预制轨道结构性能研究

High-speed Railway Pub Date : 2023-03-01 DOI: 10.1016/j.hspr.2022.11.003

Yuhang Wang , Jijun Wang , Qi Tang , Jike Tan , Guobing Lu

引用次数: 0

Incompatible thermal deformation of interlayers and corresponding damage mechanism of high-speed railway track structure 高速铁路轨道结构夹层不协调热变形及损伤机理

High-speed Railway Pub Date : 2023-03-01 DOI: 10.1016/j.hspr.2022.12.004

Guotang Zhao , Lei Zhao , Yu Liu

{"title":"Incompatible thermal deformation of interlayers and corresponding damage mechanism of high-speed railway track structure","authors":"Guotang Zhao , Lei Zhao , Yu Liu","doi":"10.1016/j.hspr.2022.12.004","DOIUrl":"https://doi.org/10.1016/j.hspr.2022.12.004","url":null,"abstract":"<div><p>In the service period, the instability of ballastless track bed are mostly related to the damage of interlayers which are mainly resulted from the incompatible thermal deformation of interlayers. The temperature field within the ballastless track bed shows significant non-uniformity due to the large difference in the materials of various structure layers, leading to a considerable difference in the force bearing of different structure layers. Unit Ballastless Track Bed (UBTB) is most significantly affected by temperature gradient. The thermal deformation of interlayers within UBTB follows the trend of ellipsoid-shape buckling under the effect of the temperature gradient, resulting in a variation of the contact relationship between structure layers and a significant periodic irregularity on the rail. When the train travels on the periodically irregular rail, the structure layers are locally contacted, and the contact zone moves with the variation of the wheel position. This wheel-followed local contact greatly magnifies the interlayer stress, causes interlayer damage, and leads to a considerable increase in the bending moment of the track slab. Continuous Ballastless Track Bed (CBTB) is most significantly affected by the overall temperature variation, which may cause damage to the joint in CBTB. Under the combined action of the overall temperature rise and the temperature gradient, the interlayer damage continuously expands, resulting in bonding failure between structural layers. The thermal force in the continuous track slabs will cause the up-heave buckling and the sudden large deformation of the track slab, and the loss of constraint boundary of the horizontal stability. For the design of a ballastless track structure, the change of bearing status and structural damage related to the incompatible thermal deformation of interlayers should be considered.</p></div>","PeriodicalId":100607,"journal":{"name":"High-speed Railway","volume":"1 1","pages":"Pages 37-46"},"PeriodicalIF":0.0,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49876338","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

MmWave extra-large-scale MIMO based active user detection and channel estimation for high-speed railway communications 高速铁路通信中基于毫米波超大规模MIMO的主动用户检测与信道估计

High-speed Railway Pub Date : 2023-03-01 DOI: 10.1016/j.hspr.2022.11.006

Anwen Liao , Ruiqi Wang , Yikun Mei , Ziwei Wan , Shicong Liu , Zhen Gao , Hua Wang , Hao Yin

{"title":"MmWave extra-large-scale MIMO based active user detection and channel estimation for high-speed railway communications","authors":"Anwen Liao , Ruiqi Wang , Yikun Mei , Ziwei Wan , Shicong Liu , Zhen Gao , Hua Wang , Hao Yin","doi":"10.1016/j.hspr.2022.11.006","DOIUrl":"https://doi.org/10.1016/j.hspr.2022.11.006","url":null,"abstract":"<div><p>The current High-Speed Railway (HSR) communications increasingly fail to satisfy the massive access services of numerous user equipment brought by the increasing number of people traveling by HSRs. To this end, this paper investigates millimeter-Wave (mmWave) extra-large scale (XL)-MIMO-based massive Internet-of-Things (IoT) access in near-field HSR communications, and proposes a block simultaneous orthogonal matching pursuit (B-SOMP)-based Active User Detection (AUD) and Channel Estimation (CE) scheme by exploiting the spatial block sparsity of the XL-MIMO-based massive access channels. Specifically, we first model the uplink mmWave XL-MIMO channels, which exhibit the near-field propagation characteristics of electromagnetic signals and the spatial non-stationarity of mmWave XL-MIMO arrays. By exploiting the spatial block sparsity and common frequency-domain sparsity pattern of massive access channels, the joint <span><math><mtext>AUD</mtext></math></span> and CE problem can be then formulated as a Multiple Measurement Vectors Compressive Sensing (MMV-CS) problem. Based on the designed sensing matrix, a B-SOMP algorithm is proposed to achieve joint AUD and CE. Finally, simulation results show that the proposed solution can obtain a better AUD and CE performance than the conventional CS-based scheme for massive IoT access in near-field HSR communications.</p></div>","PeriodicalId":100607,"journal":{"name":"High-speed Railway","volume":"1 1","pages":"Pages 31-36"},"PeriodicalIF":0.0,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49876339","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0