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Technical innovation in the “Beishan No. 1” hard rock tunnel boring machine for high-gradient spiral tunnels

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Frontiers of engineering Management 2024年第1期11卷 175-179页

作者： Ju WANG Mengxue QI Bin LONG Hongsu MA Beijing Research Institute of Uranium Geology Beijing 100029China china railway 18th Bureau group Tunnel engineering co. Ltd.Chongqing 400700China china railway co.struction Heavy Industry co. Ltd.Changsha 410100China

1 Project overview The“Beishan No.1”,the world’s first-ever hard rock Tunnel Boring Machine(TBM)tailored for high-gradient spiral tunnels,co.stitutes a pivotal element within the Beishan Underground Research Laboratory(URL)initiative in *** URL,the first URL for geological disposal of high level radioactive waste(HLW)in china,is a national key co.struction project listed in the“13th Five-Year Plan”.In 2019,subsequent to receiving approval from the china Atomic Energy Authority,the Beijing Research Institute of Uranium Geology(BRIUG),serving as the project’s owner,initiated its *** underground facility,categorized as a“third generation”URL for HLW disposal,i.e.,area-specific URL,was located in Beishan,Jiuquan City,Gansu Province,china,following more than three decades of rigorous research on site selection.

关键词： tunnel boring machine extremely hard rock co.tinuous small-radius curves high gradient equipment technology innovation

Model test study on the formation and development of underground erosion ground fissures in the Kenya Rift Valley

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Journal of Mountain Science 2022年第4期19卷 1037-1050页

作者： LIU Yang PENG Jian-bing JIANG Fu-qiang LU Quan-zhong ZHU Feng-ji Xu Qiang Department of Geological engineering Chang'an UniversityXi'an 710054China Key Laboratory of Western china Mineral Resources and Geological engineering Ministry of Education of the People's Republic of ChinaXi'an 710054China CCCC railway co.sultants group co. Ltd.Beijing 100000China china Jikan Research Institute of engineering Investigations and Design co. Ltd.Xi'an 10043China

The Kenya Rift Valley is relatively prone to underground erosion ground fissures and associated disasters,which gravely hinder local engineering co.struction and eco.omic *** this research,we performed field and experimental studies on ground fissures in the Kenya Rift Valley area,and determined the structural characteristics of underground erosion *** on a geological survey of the area,we generalized a geological model for typical ground fissures and reproduced the intermediate process of ground fissure propagation using a large-scale physical model ***,the development process of underground erosion fissures were categorized into four stages:uniform infiltration,preferential infiltration,cavity expansion,and co.lapse formation *** the development of underground erosion fissures,water co.tent was distributed symmetrically along the fissures,and these fissures acted as the primary infiltration paths of *** the ground co.lapsed,the increase in negative pore water pressure was greater,whereas the increase in positive pore water pressure was less in the shallow soil;moreover,in the deep soil,the increase in positive pore water pressure was greater than that of negative pore water ***,the earth pressure increment initially increased and then decreased with the development of *** underground erosion co.lapse,the water co.tent and pore water pressure appeared to increase and decrease *** results can be employed to predict the occurrence of underground erosion ground fissures and the resulting soil co.lapse.

关键词： Kenya Rift Valley Model test Seepage failure Underground erosion ground fissure

DEM investigation of strain behaviour and force chain evolution of gravel-sand mixtures subjected to cyclic loading

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Particuology 2022年第9期20卷 13-28页

作者： Zhihong Nie Qun Qi Xiang Wang Yangui Zhu School of Civil engineering Central South UniversityChangsha 410075China Department of Civil and Environmental engineering The Hong Kong Polytechnic UniversityHong Kong 999077China china railway First Survey and Design Institute group co. Ltd.Xi'an 710043China

The strain characteristic and load transmission of mixed granular matter are different from those of homogeneous granular *** loading renders the mechanical behaviours of mixed granular mat-ter more *** investigate the dynamic responses of gravel-sand mixtures,the discrete element method(DEM)was used to simulate the cyclic loading of gravel-sand mixtures with low fines ***,the evolution of the axial strain and volumetric strain was ***-cally,the co.rdination number and co.tact force anisotropy were studied,and the evolution of strong and weak co.tacts was explored from two dimensions of loading time and local *** simulation results show that increasing fines co.tent can accelerate the development of the axial strain and vol-umetric strain but has little effect on the evolution of co.tact *** co.tacts tend to develop along the loading boundary,presenting the spatial *** co.tacts are firstly co.trolled by co.fining pressure and then co.trolled by axial stress,while strong co.tacts are mainly co.trolled by axial stress throughout the whole cyclic *** co.pression failure occurs,the release of axial stress causes the reduction of strong co.tact proportion in all local *** findings are helpful to understand the dynamic responses of gravel-sand mixtures,especially in deformation behaviours and the Spatio-temporal evolution of co.tact forces.

关键词： Gravel-sand mixture Cyclic loading DEM Strain co.tact force

Integrated railway Smart Grid Architecture Based on Energy Routers

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Chinese Journal of Electrical engineering 2021年第4期7卷 93-106页

作者： Peng Yao Hao Wang Yijun Liu Jinping Niu Zhiwei Zhu Lin Lin Zhuhai Wanlida Electrical Automation co. Ltd.Zhuhai 519085China Guangdong Province Voltage Sag engineering Technology Research Center of Enterprise Power Supply&Distribution System Zhuhai 519085China china railway First Survey and Design Institute group co. Ltd.Xi'an 710043China

railway power system is an inseparable part of the power system,therefore,the intelligent architecture of the railway power system should also be focused *** unique power supply characteristics of the railway power system are analyzed and integrated railway smart grid architecture based on energy routers is ***,three co.responding resilient mode co.trol methods are suggested for the proposed *** the fourth section,a simulation model co.responding to the resilient co.trol mode is built and the simulation results prove the feasibility of the proposed co.trol ***,for the novel network-co.nected backbone router(NCBR),a 1000 kVA,27.5/10 kV NCBR engineering prototype is used to prove its effectiveness in practical ***,a differentiation analysis is given,followed by co.clusions regarding the traditional power system and proposed system.

关键词： railway traction power system railway electric distribution system integrated railway smart grid architecture energy migration router network-co.nected backbone router engineering prototype

World’s first implementation of close-fit pipe jacking of twin tunnels for co.struction of subway station--Innovation in equipment and co.struction technology

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Frontiers of engineering Management 2024年第2期11卷 369-376页

作者： Xiangsheng CHEN Bo SUN Wei LI Yongzhao WU Wenpeng ZHOU Meng FENG Lei WANG Wensheng YANG Xiang WU Weiyi LONG Dong SU Shenzhen Univeristy Shenzhen 518060China Shenzhen Metro group co. Ltd.Shenzhen 518031China Shenzhen Municipal Design&Research co. Ltd.Shenzhen 518000China Sinohydro Bureau 11 co. Ltd.Zhengzhou 450001China china railway engineering Equipment group co. LTD.Zhengzhou 450000China Shenzhen University Shenzhen 518060China

1 Project overview The Shasan station of Phase II of Shenzhen’s urban rail transit Line 12 is situated in Bao’an District,*** co.prises a two-level underground island platform station,measuring 212 m in length,and 22.6 m in width,with an overburden thickness of about 7.0 ***.1 illustrates the presence of a large underground reinforced co.crete stormwater culvert,measuring 11.5 m by 3.6 m,traversing the station’s center.

关键词： Subway station close-fit pipe jacking of twin tunnels modular rectangular pipe jacking machine Structural Transformation equipment co.struction

Toughness improvement mechanism and evaluation of cement co.crete for road pavement:A review

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Journal of Road engineering 2023年第2期3卷 125-140页

作者： Mingjing Fang Yiming Chen Yungang Deng Zhe Wang Mengjun Zhu School of Civil engineering and Architecture Wuhan University of TechnologyWuhan 430070China Transportation Branch China Railway Siyuan Survey and Design GroupCo.Ltd.Wuhan 430063China

Traditional cement co.crete has the disadvantages of low tensile strength,poor toughness,and rapid development of cracks while cracking,which causes a significantly negative influence on the safety and durability of co.crete road *** paper presents a state-of-the-art review of toughness improvement mechanisms and evaluation methods of cement co.crete for road *** review indicates that(i)The performance of co.crete material depends on its material co.position and internal *** size,cement properties and admixtures are the main factors of co.crete toughness.(ii)The inco.poration of rubber or fiber in pavement co.crete improves the toughness of co.crete ***,these additions must be maintained within a reasonable *** amount of rubber and fiber are enco.raged not more than 30%of the volume of fine aggregate and 2%of the volume of co.crete,respectively.(iii)The toughness of pavement co.crete material includes the toughness regarding bending,impact and *** toughness of cement co.crete for highway and municipal pavement is generally evaluated by bending and fracture toughness,while the toughness of airfield pavement co.crete is more focused on impact toughness.(iv)The toughening measures of cement co.crete for road pavement are mainly mixed with rubber or fiber,while these two materials have their defects,and the application of hightoughness cement co.crete in the actual road still faces many *** example,the synergistic effect of rubber and fiber,the development and application of new flexible admixtures,and the formulation of the toughness index of pavement cement co.crete materials need further research.

关键词： Cement co.crete Road pavement Toughness Toughness evaluation method

Sensor placement for structural damage detection with modal data

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Journal of Harbin Institute of Technology(New Series) 2010年第3期17卷 297-302页

作者：孙小猛冯新周晶闫子才 State Key Laboratory of co.stal and Offshore engineering Dalian University of Technology china railway No.4 engineering group co. ltd

A new method is presented for prioritizing sensor locations for structural health monitoring (SHM). In view of the needs of SHM and damage detection,sensor locations are optimized for the purpose of both sensitivity for local damages and independence of the target mode. However,the two different optimization criterions lead to an inco.sistency of the optimal result. co.sidering the structural response changes that result from damage,the relationship between the structural response and damage is deduced from the structural motion equation by a quasi-analytical mode. Based on the harmony between damage identifiability and mode observability,an object function is set up,including the information of mode independence and damage sensitivity. Utilizing the technique of singular value deco.position,an interior algorithm for the optimum sensor placement is proposed with the multiple objective criterions of minimizing the co.dition number of co.fficient matrix and maximizing the fisher information matrix. A numerical example shows that this approach can effectively avoid the co.tradiction between the two different optimization criterions. co.paring with the result of single object,the result of damage detection from the optical sensor locations is much more accurate.

关键词： sensor placement damage sensitivity mode observability fisher information matrix

A novel refined dynamic model of high-speed maglev train-bridge co.pled system for random vibration and running safety assessment

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Journal of Central South University 2024年第7期31卷 2532-2544页

作者： MAO Jian-feng LI Dao-hang YU Zhi-wu CAI Wen-feng GUO Wei ZHANG Guang-wen School of Civil engineering Central South UniversityChangsha 410075China National engineering Research Center of High-speed railway co.struction Technology Changsha 410075China china railway group Limited Beijing 100039China china railway eryuan engineering group co. Ltd.Chengdu 610031China

Running safety assessment and tracking irregularity parametric sensitivity analysis of high-speed maglev train-bridge system are of great co.cern,especially need perfect refinement models in which all properties can be well characterized based on various stochastic excitations.A three-dimensional refined spatial random vibration analysis model of high-speed maglev train-bridge co.pled system is established in this paper,in which multi-source uncertainty excitation can be co.sidered simultaneously,and the probability density evolution method(PDEM)is adopted to reveal the system-specific uncertainty dynamic *** motion equation of the maglev vehicle model is co.posed of multi-rigid bodies with a total 210-degrees of freedom for each vehicle,and a refined electromagnetic force-air gap model is used to acco.nt for the interaction and co.pling effect between the moving train and track beam bridges,which are directly established by using finite element *** model is proven to be applicable by co.paring with Monte Carlo *** applying the proposed stochastic framework to the high maglev line,the random dynamic responses of maglev vehicles running on the bridges are studied for running safety and stability ***,the effects of track irregularity wavelength range under different amplitude and running speeds on the co.pled system are *** results show that the augmentation of train speed will move backward the sensitive wavelength interval,and track irregularity amplitude influences the response remarkably in the sensitive interval.

关键词： maglev train-bridge interaction electromagnetic force-air gap model stochastic dynamic analysis running safety assessment probability density evolution method

Simulation Analysis and Verifcation of Temperature and Stress of Wheel-Mounted Brake Disc of a High-Speed Train

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Chinese Journal of Mechanical engineering 2022年第4期35卷 331-339页

作者： Junsheng Qu Wenjing Wang Ziyu Dong Wei Shan School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Department of Loco.otive&Vehicle China National Railway Group Co.LtdBeijing 100844China

During the braking process,a large amount of heat energy is generated at the friction surfaces between the brake disc and pads and rapidly dissipates into the disc *** this paper,a three-dimensional thermo-mechanical co.pling model of high-speed wheel-mounted brake discs co.taining bolted joints and co.tact relationships is *** direct co.pling method is used to analyze the temperature and stress of the brake discs during an emergency braking event with an initial speed of 300 km/h.A full-scale bench test is also co.ducted to monitor the temperatures of the friction ring and bolted *** simulation result shows that the surface temperature of the friction ring reaches its peak value of 414°C after 102 s of braking,which agrees well with the bench test *** maximum alternating thermal stress occurs in the bolt hole where the maximum circumferential co.pressive stress is−658 MPa and the maximum circumferential tensile stress is 134 *** the braking process,the out-of-plane deformation of the middle part of the friction ring is larger than that of the edge,which increases the axial tensile load of the co.necting *** work provides support for the design of brake discs and co.necting bolts.

关键词： High speed train Wheel-mounted brake disc Temperature feld Stress feld Thermo-mechanical co.pling model Bolt