{"title":"Exploring the feasibility of prestressed anchor cables as an alternative to temporary support in the excavation of super-large-span tunnel","authors":"Shunhua Zhou, Yuyin Jin, Zhiyao Tian, Chunhua Zou, Heming Zhao, Zengrun Miao","doi":"10.1007/s40534-024-00340-w","DOIUrl":"https://doi.org/10.1007/s40534-024-00340-w","url":null,"abstract":"<p>Excavating super-large-span tunnels in soft rock masses presents significant challenges. To ensure safety, the sequential excavation method is commonly adopted. It utilizes internal temporary supports to spatially partition the tunnel face and divide the excavation into multiple stages. However, these internal supports generally impose spatial constraints, limiting the use of large-scale excavation equipment and reducing construction efficiency. To address this constraint, this study adopts the “Shed-frame” principle to explore the feasibility of an innovative support system, which aims to replace internal supports with prestressed anchor cables and thus provide a more spacious working space with fewer internal obstructions. To evaluate its effectiveness, a field case involving the excavation of a 24-m span tunnel in soft rock is presented, and an analysis of extensive field data is conducted to study the deformation characteristics of the surrounding rock and the mechanical behavior of the support system. The results revealed that prestressed anchor cables integrated the initial support with the shed, creating an effective “shed-frame” system, which successively maintained tunnel deformation and frame stress levels within safe regulatory bounds. Moreover, the prestressed anchor cables bolstered the surrounding rock effectively and reduced the excavation-induced disturbance zone significantly. In summary, the proposed support system balances construction efficiency and safety. These field experiences may offer valuable insights into the popularization and further development of prestressed anchor cable support systems.</p>","PeriodicalId":41270,"journal":{"name":"Railway Engineering Science","volume":null,"pages":null},"PeriodicalIF":6.3,"publicationDate":"2024-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141259581","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Qiliang Li, Yuqing Sun, Menghan Ouyang, Zhigang Yang
{"title":"Flow and sound fields of scaled high-speed trains with different coach numbers running in long tunnel","authors":"Qiliang Li, Yuqing Sun, Menghan Ouyang, Zhigang Yang","doi":"10.1007/s40534-024-00330-y","DOIUrl":"https://doi.org/10.1007/s40534-024-00330-y","url":null,"abstract":"<p>Segregated incompressible large eddy simulation and acoustic perturbation equations were used to obtain the flow field and sound field of 1:25 scale trains with three, six and eight coaches in a long tunnel, and the aerodynamic results were verified by wind tunnel test with the same scale two-coach train model. Time-averaged drag coefficients of the head coach of three trains are similar, but at the tail coach of the multi-group trains it is much larger than that of the three-coach train. The eight-coach train presents the largest increment from the head coach to the tail coach in the standard deviation (STD) of aerodynamic force coefficients: 0.0110 for drag coefficient (<i>C</i><sub>d</sub>), 0.0198 for lift coefficient (<i>C</i><sub>l</sub>) and 0.0371 for side coefficient (<i>C</i><sub>s</sub>). Total sound pressure level at the bottom of multi-group trains presents a significant streamwise increase, which is different from the three-coach train. Tunnel walls affect the acoustic distribution at the bottom, only after the coach number reaches a certain value, and the streamwise increase in the sound pressure fluctuation of multi-group trains is strengthened by coach number. Fourier transform of the turbulent and sound pressures presents that coach number has little influence on the peak frequencies, but increases the sound pressure level values at the tail bogie cavities. Furthermore, different from the turbulent pressure, the first two sound pressure proper orthogonal decomposition (POD) modes in the bogie cavities contain 90% of the total energy, and the spatial distributions indicate that the acoustic distributions in the head and tail bogies are not related to coach number.</p>","PeriodicalId":41270,"journal":{"name":"Railway Engineering Science","volume":null,"pages":null},"PeriodicalIF":6.3,"publicationDate":"2024-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141259477","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yihao Chi, Hong Xiao, Yang Wang, Zhihai Zhang, Mahantesh M. Nadakatti
{"title":"Experimental study and numerical simulation of the impact of under-sleeper pads on the dynamic and static mechanical behavior of heavy-haul railway ballast track","authors":"Yihao Chi, Hong Xiao, Yang Wang, Zhihai Zhang, Mahantesh M. Nadakatti","doi":"10.1007/s40534-024-00337-5","DOIUrl":"https://doi.org/10.1007/s40534-024-00337-5","url":null,"abstract":"<p>Laying the under-sleeper pad (USP) is one of the effective measures commonly used to delay ballast degradation and reduce maintenance workload. To explore the impact of application of the USP on the dynamic and static mechanical behavior of the ballast track in the heavy-haul railway system, numerical simulation models of the ballast bed with USP and without USP are presented in this paper by using the discrete element method (DEM)—multi-flexible body dynamic (MFBD) coupling analysis method. The ballast bed support stiffness test and dynamic displacement tests were carried out on the actual operation of a heavy-haul railway line to verify the validity of the models. The results show that using the USP results in a 43.01% reduction in the ballast bed support stiffness and achieves a more uniform distribution of track loads on the sleepers. It effectively reduces the load borne by the sleeper directly under the wheel load, with a 7.89% reduction in the pressure on the sleeper. Furthermore, the laying of the USP changes the lateral resistance sharing ratio of the ballast bed, significantly reducing the stress level of the ballast bed under train loads, with an average stress reduction of 42.19 kPa. It also reduces the plastic displacement of ballast particles and lowers the peak value of rotational angular velocity by about 50% to 70%, which is conducive to slowing down ballast bed settlement deformation and reducing maintenance costs. In summary, laying the USP has a potential value in enhancing the stability and extending the lifespan of the ballast bed in heavy-haul railway systems.</p>","PeriodicalId":41270,"journal":{"name":"Railway Engineering Science","volume":null,"pages":null},"PeriodicalIF":6.3,"publicationDate":"2024-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141151943","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
O. Nabochenko, M. Sysyn, Norman Krumnow, Szabolcs Fischer
{"title":"Mechanism of cross-level settlements and void accumulation of wide and conventional sleepers in railway ballast","authors":"O. Nabochenko, M. Sysyn, Norman Krumnow, Szabolcs Fischer","doi":"10.1007/s40534-024-00329-5","DOIUrl":"https://doi.org/10.1007/s40534-024-00329-5","url":null,"abstract":"","PeriodicalId":41270,"journal":{"name":"Railway Engineering Science","volume":null,"pages":null},"PeriodicalIF":6.3,"publicationDate":"2024-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140676929","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"NeTrainSim: a network-level simulator for modeling freight train longitudinal motion and energy consumption","authors":"Ahmed S. Aredah, Karim Fadhloun, H. Rakha","doi":"10.1007/s40534-024-00331-x","DOIUrl":"https://doi.org/10.1007/s40534-024-00331-x","url":null,"abstract":"","PeriodicalId":41270,"journal":{"name":"Railway Engineering Science","volume":null,"pages":null},"PeriodicalIF":6.3,"publicationDate":"2024-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140723004","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Philipe Augusto de Paula Pacheco, M. Magelli, Matheus Valente Lopes, P. Corrêa, N. Zampieri, N. Bosso, A. A. dos Santos
{"title":"The effectiveness of different wear indicators in quantifying wear on railway wheels of freight wagons","authors":"Philipe Augusto de Paula Pacheco, M. Magelli, Matheus Valente Lopes, P. Corrêa, N. Zampieri, N. Bosso, A. A. dos Santos","doi":"10.1007/s40534-024-00334-8","DOIUrl":"https://doi.org/10.1007/s40534-024-00334-8","url":null,"abstract":"","PeriodicalId":41270,"journal":{"name":"Railway Engineering Science","volume":null,"pages":null},"PeriodicalIF":6.3,"publicationDate":"2024-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140721815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Simplified prediction models for acoustic installation effects of train-mounted equipment","authors":"David J. Thompson, Dong Zhao, G. Squicciarini","doi":"10.1007/s40534-024-00333-9","DOIUrl":"https://doi.org/10.1007/s40534-024-00333-9","url":null,"abstract":"","PeriodicalId":41270,"journal":{"name":"Railway Engineering Science","volume":null,"pages":null},"PeriodicalIF":6.3,"publicationDate":"2024-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140725853","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Parametric investigation of railway fastenings into the formation and mitigation of short pitch corrugation","authors":"Pan Zhang, Shaoguang Li, R. Dollevoet, Zili Li","doi":"10.1007/s40534-024-00332-w","DOIUrl":"https://doi.org/10.1007/s40534-024-00332-w","url":null,"abstract":"","PeriodicalId":41270,"journal":{"name":"Railway Engineering Science","volume":null,"pages":null},"PeriodicalIF":6.3,"publicationDate":"2024-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140234944","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. Ferreira, P. Montenegro, José Rui Pinto, António Abel Henriques, R. Calçada
{"title":"A discussion about the limitations of the Eurocode’s high-speed load model for railway bridges","authors":"G. Ferreira, P. Montenegro, José Rui Pinto, António Abel Henriques, R. Calçada","doi":"10.1007/s40534-023-00321-5","DOIUrl":"https://doi.org/10.1007/s40534-023-00321-5","url":null,"abstract":"","PeriodicalId":41270,"journal":{"name":"Railway Engineering Science","volume":null,"pages":null},"PeriodicalIF":6.3,"publicationDate":"2024-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140423155","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}