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Experimental investigation on the invert stability of operating railway tunnels with different drainage systems using 3D printing technology 被引量:3
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作者 Linyi Li Junsheng Yang +3 位作者 Jinyang Fu Shuying Wang Cong Zhang Maolong Xiang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2022年第5期1470-1485,共16页
In recent years, the invert anomalies of operating railway tunnels in water-rich areas occur frequently,which greatly affect the transportation capacity of the railway lines. Tunnel drainage system is a crucial factor... In recent years, the invert anomalies of operating railway tunnels in water-rich areas occur frequently,which greatly affect the transportation capacity of the railway lines. Tunnel drainage system is a crucial factor to ensure the invert stability by regulating the external water pressure(EWP). By means of a threedimensional(3D) printing model, this paper experimentally investigates the deformation behavior of the invert for the tunnels with the traditional drainage system(TDS) widely used in China and its optimized drainage system(ODS) with bottom drainage function. Six test groups with a total of 110 test conditions were designed to consider the design factors and environmental factors in engineering practice,including layout of the drainage system, blockage of the drainage system and groundwater level fluctuation. It was found that there are significant differences in the water discharge, EWP and invert stability for the tunnels with the two drainage systems. Even with a dense arrangement of the external blind tubes, TDS was still difficult to eliminate the excessive EWP below the invert, which is the main cause for the invert instability. Blockage of drainage system further increased the invert uplift and aggravated the track irregularity, especially when the blockage degree is more than 50%. However, ODS can prevent these invert anomalies by reasonably controlling the EWP at tunnel bottom. Even when the groundwater level reached 60 m and the blind tubes were fully blocked, the invert stability can still be maintained and the railway track experienced a settlement of only 1.8 mm. Meanwhile, the on-site monitoring under several rainstorms further showed that the average EWP of the invert was controlled within 84 k Pa, while the maximum settlement of the track slab was only 0.92 mm, which also was in good agreement with the results of model test. 展开更多
关键词 Operating railway tunnels Invert stability Tunnel drainage system Three-dimensional(3D)printing technology Model test
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Reasonable compensation coefficient of maximum gradient in long railway tunnels 被引量:1
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作者 Sirong YI Liangtao NIE Yanheng CHEN Fangfang QIN 《Journal of Modern Transportation》 2011年第1期12-18,共7页
This paper deals with the theory and calculation methods for compensation of the gradient in railway tunnels through theoretical analysis, numerical calculation, and statistic regression methods. On the basis of the p... This paper deals with the theory and calculation methods for compensation of the gradient in railway tunnels through theoretical analysis, numerical calculation, and statistic regression methods. On the basis of the principle that the resultant force is zero, the formula of the maximum calculated gradient was derived for the freight and passenger line and high-speed passenger special line. The formula of aerodynamic drag in tunnel is provided using the domestic and foreign relevant experimental investigations, and revised with modem train and engineering parameters. A calculation model of aerodynamic drag when the train goes through a single-tracked tunnel was built. Finally, the concept of maximum calculated gradient was adopted to revise the formula for compensation of the gradient in railway tunnels. 展开更多
关键词 railway tunnel maximum gradient PROFILE gradient compensation
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Fatigue damage analysis of ballastless slab track in heavy-haul railway tunnels 被引量:2
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作者 Zi-qiang Li Zheng Li +2 位作者 Wei-wei Huang Hong-rui Zhang Hang Zhang 《Underground Space》 SCIE EI 2022年第3期440-452,共13页
A ballastless slab track,which is commonly used in the track structures of heavy-haul railway tunnels,was analysed based on field measurement data of the Fuyingzi Tunnel on the Zhangtang Railway.In accordance with the... A ballastless slab track,which is commonly used in the track structures of heavy-haul railway tunnels,was analysed based on field measurement data of the Fuyingzi Tunnel on the Zhangtang Railway.In accordance with the measured data,the dynamic load thresholds and distributions on the surface and bottom of the ballastless slab track were investigated.A fatigue damage analysis of the ballastless slab track was performed based on the dynamic load time–history curve.The results show that the ballastless slab track can accomplish train load attenuation and reduce the dynamic load from heavy-haul trains by 47.22%from the surface to the bottom.In addition,the distribution at the bottom of the ballastless slab track exhibited a triangular shape,and the dynamic load threshold at the line centre accounted for 78.67%of that at the track position.Meanwhile,the distribution at the surface was saddle-shaped;the dynamic load threshold at the track position accounted for 79.55%of that at the line centre position.The fatigue damage of the ballastless slab track was analysed effectively by combining the measured data and the linear fatigue damage theory.Moreover,the accuracy of the calculation results was verified based on the measured dynamic stress of the ballastless slab track structure.The dynamic action of the train load led to more-concentrated damage to the track bed,and the damage occurred earlier than that in the ordinary line.The axle load was the primary influencing factor of the track bed fatigue damage,and the damage mainly occurred in the track position.These results provide a theoretical basis for performing stress analysis and designing parameters for ballastless slab tracks in heavy-haul railway tunnels. 展开更多
关键词 Heavy-haul railway tunnel Numerical simulation results Ballastless slab track Fatigue damage
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Deterioration of concrete in railway tunnel suffering from sulfate attack 被引量:10
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作者 龙广成 谢友均 +1 位作者 邓德华 李小坤 《Journal of Central South University》 SCIE EI CAS 2011年第3期881-888,共8页
For the sake of understanding the deterioration behavior of concrete in actual railway tunnel structures subjected to aggressive sulfate medium in practice,detailed field investigations and tested analysis on sprayed ... For the sake of understanding the deterioration behavior of concrete in actual railway tunnel structures subjected to aggressive sulfate medium in practice,detailed field investigations and tested analysis on sprayed concrete linings of approximately 40-year-old railway tunnels in environments containing sulfate ion were carried out,respectively.The results show that the deterioration of concretes in the investigated area is serious,which involves complicated physicochemical process between the sulfate salt and concrete.Among them,the secondary sulfateminerals such as gypsum formation under very high concentration sulfate ion condition by accumulating and evaporation process dominate,followed by the crystallization of sulfate salt and formation of thaumasite. 展开更多
关键词 sulfate attack CONCRETE railway tunnel secondary sulfate minerals salt crystallization
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Model test on dynamic characteristics of invert and foundation soils of high-speed railway tunnel 被引量:13
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作者 Huang Juan Yuan Tieying +2 位作者 Peng Limin Yu Jun Ding Zude 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2015年第3期549-559,共11页
A dynamic model test(CL = 4) at different velocities of train,namely different loading frequencies,is carried out to study the dynamic characteristics of a high-speed railway tunnel invert and its foundation soils.Not... A dynamic model test(CL = 4) at different velocities of train,namely different loading frequencies,is carried out to study the dynamic characteristics of a high-speed railway tunnel invert and its foundation soils.Not only are the accelerations,dynamic coefficients,dynamic stresses of the invert and foundation soils emphatically analyzed,their relationship with the velocity of the train are discussed in detail.Through laboratory testing,the attenuation of vibration propagating from up the rails is obtained and the calculation formula of the speed influence coefficient of the tunnel invert is preliminarily established.The depth of the foundation soils influenced by vibration is also determined in this study.It is shown that the responses of the tunnel invert and foundation soils to vibration are slightly increased with the velocity of the train;circumferential stresses in the bottom of the invert are tensile stresses and maximum stresses appear under the foot of the rails;the dynamic soil pressures of the foundation decrease quickly with the distance away from the tunnel invert and an exponential relationship exists between them. 展开更多
关键词 high speed railway tunnel dynamic characteristic M
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Railway tunnel concrete lining damaged by formation of gypsum,thaumasite and sulfate crystallization products in southwest of China 被引量:7
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作者 马昆林 龙广成 谢友均 《Journal of Central South University》 SCIE EI CAS 2012年第8期2340-2347,共8页
The railway tunnel concrete lining exposed to sulfate-bearing groundwater beyond 40 years in southwest of China was investigated. Field investigation, sulfate ions content and corroded products analysis, macro/microsc... The railway tunnel concrete lining exposed to sulfate-bearing groundwater beyond 40 years in southwest of China was investigated. Field investigation, sulfate ions content and corroded products analysis, macro/microscopic test were carried out. Results show that under the tunnel concrete lining structure and its served environmental conditions, sulfate solutions permeate concrete lining and accumulate on windward-side of concrete lining, resulting in the increase of sulfate ions content on windward-side and the diffusion of sulfate ions from windward-side to waterward-side, which cause the concrete lining of windward-side damaged seriously but the waterward-side of concrete lining is still in perfect condition. It is confirmed that structural characteristic of tunnel and environmental conditions lead to physical attack with the leaching of concrete and sodium sulfate crystallization as well as chemical corrosion with formation of gypsum in high sulfate concentration and formation of thaumasite in proper temperature rather than formation of ettringite. These achievements can provide academic and technical supports for understanding the deterioration mechanism of concrete lining as well as constructing railway tunnel under sulfate attack. 展开更多
关键词 railway tunnel concrete lining sulfate attack deterioration mechanism
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Aerodynamic effects on a railway tunnel with partially changed cross-sectional area 被引量:4
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作者 LI Wen-hui LIU Tang-hong +3 位作者 MARTINEZ-VAZQUEZ Pedro XIA Yu-tao CHEN Zheng-wei GUO Zi-jian 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第8期2589-2604,共16页
The present study numerically explored the aerodynamic performance of a novel railway tunnel with a partially reduced cross-section.The impact of the reduction rate of the tunnel cross-section on wave transmissions wa... The present study numerically explored the aerodynamic performance of a novel railway tunnel with a partially reduced cross-section.The impact of the reduction rate of the tunnel cross-section on wave transmissions was analyzed based on the three-dimensional,unsteady,compressible,and RNG k-εturbulence model.The results highlight that the reduction rate(S)most affects pressure configurations at the middle tunnel segment,followed by the enlarged segments near access,and finally the exit.The strength of the newly generated compression wave at the tunnel junction where the cross-section abruptly changes increases exponentially with the decrease of the cross-sectional area.The maximum peak-to-peak pressureΔP on the tunnel and train surface for non-uniform tunnels is reduced by 10.7%and 13.8%,respectively,compared with those of equivalent uniform tunnels.Overall,the economic analysis suggests that the aerodynamic performance of the developed tunnel prototype surpasses those conventional tunnels based on the same excavated volume. 展开更多
关键词 high-speed train railway tunnel CROSS-SECTION transient pressure blockage ratio
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In Situ Experiments on Supporting Load Effect of Large-span Deep Tunnels in Hard Rock 被引量:4
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作者 HE Ben-guo ZHU Yong-quan +2 位作者 SUN Ming-lei LIU Hong-yan ZHANG Zhi-qiang 《Journal of Mountain Science》 SCIE CSCD 2013年第6期1125-1136,共12页
A section of the Nanliang high speed railway tunnel on Shijiazhuang-Taiyuan high-speed passenger railway line in China was instrumented and studied for its mechanical properties and performances. The cross section for... A section of the Nanliang high speed railway tunnel on Shijiazhuang-Taiyuan high-speed passenger railway line in China was instrumented and studied for its mechanical properties and performances. The cross section for the tunnel was300 m2and is classified as the largest cross section for railway tunnels in China. Through in situ experimental studies, mechanistic properties of the tunnel were identified, including the surrounding rock pressure, convergences along tunnel perimeter and safety of primary support and lining structure.Based on the field measured data, the surrounding rock pressure demand for large-span deep tunnel in hard rock is recommended as double peak type in the vertical direction and fold line type was recommended for horizontal pressure. The results suggested that Promojiyfakonov's theory was most close to the monitored value. Specific recommendations were also generated for the use of bolts in tunnel structures.Numerical simulation was used to evaluate the safety of the tunnel and it confirmed that the current design can satisfy the requirement of the current code. 展开更多
关键词 Large-span tunnel railway tunnel Surrounding rock pressure Load distribution In situ experiment
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A Study of the Suitable Measurement Location and Metrics for Assessing the Vibration Source Strength Based on the Field-Testing Data of Nanchang Underground Railway 被引量:4
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作者 Ling Zhang Xiaoyan Lei +1 位作者 Jian Jiang Qingsong Feng 《Sound & Vibration》 2018年第5期22-27,共6页
Underground railway vibration source strength is one of the key values used for environmental impact assessment and the evaluation of mitigation measure’s performance.However,currently there is no international stand... Underground railway vibration source strength is one of the key values used for environmental impact assessment and the evaluation of mitigation measure’s performance.However,currently there is no international standard of measuring the underground railway vibration source strength for such purposes.The available local standards and industrial guidelines do not agree on measurement locations as well as the metrics for presenting the source strength.This has caused many confusions.This paper aims to study the suitable measurement location and metrics using the data from a large scale field-testing carried out at the Nanchang underground railway(Metro Line 1,China)in 2017.200 passing trains were recorded during the test at two different sections of the railway line,one with the spring floating slab installed and the other without.Three locations were chosen at each section,including one in the middle of the track and two on the tunnel wall at different heights.Based on the results of statistical analysis,the maximum of z-weighted vertical vibration level(VLzmax)obtained at a lower measurement location on the tunnel wall is the best for representing the underground railway vibration source strength,which is 76.66 dB obtained from this study. 展开更多
关键词 Underground railway tunnel vibration source strength floating slab statistics analysis
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Finite-State Markov Wireless Channel Modeling for Railway Tunnel Environments 被引量:3
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作者 Cuiran Li Ling Liu Jianli Xie 《China Communications》 SCIE CSCD 2020年第2期30-39,共10页
In recent years,high-speed railways(HSRs)have developed rapidly with a high transportation capacity and high comfort level.A tunnel is a complex high-speed rail terrain environment.It is very important to establish an... In recent years,high-speed railways(HSRs)have developed rapidly with a high transportation capacity and high comfort level.A tunnel is a complex high-speed rail terrain environment.It is very important to establish an accurate channel propagation model for a railway tunnel environment to improve the safety of HSR operation.In this paper,a method for finite-state Markov chain(FSMC)channel modeling with least squares fitting based on non-uniform interval division is proposed.First,a path loss model is obtained according to measured data.The communication distance between the transmitter and receiver in the tunnel is non-uniformly divided into several large non-overlapping intervals based on the path loss model.Then,the Lloyd-Max quantization method is used to determine the threshold of the signal-to-noise ratio(SNR)and the channel state quantization value and obtain the FSMC state transition probability matrix.Simulation experiments show that the proposed wireless channel model has a low mean square error(MSE)and can accurately predict the received signal power in a railway tunnel environment. 展开更多
关键词 railway tunnel FSMC channel model SNR path loss
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Prototype test study on mechanical characteristics of segmental lining structure of underwater railway shield tunnel 被引量:5
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作者 He Chuan Feng Kun Yan Qixiang 《Engineering Sciences》 EI 2014年第2期65-74,共10页
Based on the first unde rwater railway shield tunnel, the Shiziyang shield tunnel of Guangzhou Zhu- jiang River, the prototype test was carried out against its segmental lining structure by using "multi-function shie... Based on the first unde rwater railway shield tunnel, the Shiziyang shield tunnel of Guangzhou Zhu- jiang River, the prototype test was carried out against its segmental lining structure by using "multi-function shield tunnel structure test system". And the mechanical characteristics of segmental lining structure using straight assembling and staggered assembling were studied deeply. The results showed that, the mechanical characteristics of segmental lining structure varied with the water pressures; especially after cracking, the high water pressure played a significant role in slowing down the growing inner force and deformation. It also testi- fied that the failure characteristics varied with straight assembling structure and staggered assembling structure. Shear thilurc often occurred near longitudinal seam when using straight assembling. 展开更多
关键词 underwater railway shield tunnel segmental lining structure prototype test tenon joint failure characteristics
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Vehicle–track–tunnel dynamic interaction:a finite/infinite element modelling method 被引量:6
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作者 Lei Xu Wanming Zhai 《Railway Engineering Science》 2021年第2期109-126,共18页
The aim of this study is to develop coupled matrix formulations to characterize the dynamic interaction between the vehicle,track,and tunnel.The vehicle–track coupled system is established in light of vehicle–track ... The aim of this study is to develop coupled matrix formulations to characterize the dynamic interaction between the vehicle,track,and tunnel.The vehicle–track coupled system is established in light of vehicle–track coupled dynamics theory.The physical characteristics and mechanical behavior of tunnel segments and rings are modeled by the finite element method,while the soil layers of the vehicle–track–tunnel(VTT)system are modeled as an assemblage of 3-D mapping infinite elements by satisfying the boundary conditions at the infinite area.With novelty,the tunnel components,such as rings and segments,have been coupled to the vehicle–track systems using a matrix coupling method for finite elements.The responses of sub-systems included in the VTT interaction are obtained simultaneously to guarantee the solution accuracy.To relieve the computer storage and save the CPU time for the large-scale VTT dynamics system with high degrees of freedoms,a cyclic calculation method is introduced.Apart from model validations,the necessity of considering the tunnel substructures such as rings and segments is demonstrated.In addition,the maximum number of elements in the tunnel segment is confirmed by numerical simulations. 展开更多
关键词 Vehicle-track-tunnel interaction railway tunnel Finite elements Infinite elements Dynamic modelling
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Scientific problems and research proposals for Sichuan–Tibet railway tunnel construction 被引量:8
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作者 Dingli Zhang Zhenyu Sun Qian Fang 《Underground Space》 SCIE EI 2022年第3期419-439,共21页
The Sichuan–Tibet railway construction has received significant attention from both China and abroad.The new section from Ya’an to Nyingchi is about 1018.6 km long,including 69 tunnels with a total length of 841.7 k... The Sichuan–Tibet railway construction has received significant attention from both China and abroad.The new section from Ya’an to Nyingchi is about 1018.6 km long,including 69 tunnels with a total length of 841.7 km.The longest tunnel(Yigong tunnel)is 42.4 km long.The successful construction of the Sichuan–Tibet railway depends largely on tunnel construction.Due to the complex conditions,tunnel construction for the Sichuan–Tibet railway poses great challenges to the research community.This paper aims to illustrate the necessity of interdisciplinary and joint research to solve problems associated with tunnel construction that will be encountered in the immediate future and facilitate the communication and exchange of ideas between disciplines.To this end,based on a systematic analysis of the available data related to Sichuan–Tibet railway tunnels,six major aspects of the geology,environment,and engineering conditions are identified.Next,based on the engineering responses from the Sichuan–Tibet railway tunnels,potential technical problems and risk characteristics are predicted and evaluated.Further,six key scientific issues are identified and discussed based on a coupled multi-layer analysis of essential tunnel engineering issues.Finally,research directions,technical ideas,and research methods that should be carried out for this project are proposed. 展开更多
关键词 Sichuan–Tibet railway tunnels Key scientific problems Complex stress environment Deformation mechanism of surrounding rock Dynamic response
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Comparative analysis between single-train passing and double-train intersection in a tunnel
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作者 Jianming DU Qian FANG +1 位作者 Xuan ZHANG Hualao WANG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2024年第5期429-442,共14页
Aerodynamic pressure significantly impacts the scientific evaluation of tunnel service performance.The aerodynamic pressure of two trains running in a double-track tunnel is considerably more complicated than that of ... Aerodynamic pressure significantly impacts the scientific evaluation of tunnel service performance.The aerodynamic pressure of two trains running in a double-track tunnel is considerably more complicated than that of a single train.We used the numerical method to investigate the difference in aerodynamic pressure between a single train and two trains running in a double-track tunnel.First,the numerical method was verified by comparing the results of numerical simulation and on-site monitoring.Then,the characteristics of aerodynamic pressure were studied.Finally,the influence of various train-tunnel factors on the characteristics of aerodynamic pressure was investigated.The results show that the aerodynamic pressure variation can be divided into stage I:irregular pressure fluctuations before the train tail leaves the tunnel exit,and stage II:periodic pressure declines after the train tail leaves the tunnel exit.In addition,the aerodynamic pressure simultaneously jumps positively or drops negatively for a single train or two trains running in double-track tunnel scenarios.The pressure amplitude in the two-train case is higher than that for a single train.The maximum positive peak pressure difference(P_(STP))and maximum negative peak pressure difference(P_(STN))increase as train speed rises to the power from 2.256 to 2.930 in stage I.The P_(STP) and P_(STN) first increase and then decrease with the increase of tunnel length in stage I.The P_(STP) and P_(STN) increase as the blockage ratio rises to the power from 2.032 to 2.798 in stages I and II. 展开更多
关键词 railway tunnel Aerodynamic effect Pressure characteristic Train speed Tunnel length Blockage ratio
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Characteristics of a compression wave propagating over porous plate wall in a high-speed railway tunnel 被引量:1
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作者 T.Aoki J.Yamamoto K.Nagatani 《Journal of Thermal Science》 SCIE EI CAS CSCD 2008年第3期218-223,共6页
A pressure wave is generated ahead of a high-speed train, while entering a tunnel. This pressure wave propagates to the tunnel exit and spouts as a micro-pressure wave, which causes an exploding sound. From the fact t... A pressure wave is generated ahead of a high-speed train, while entering a tunnel. This pressure wave propagates to the tunnel exit and spouts as a micro-pressure wave, which causes an exploding sound. From the fact that the ballast track tunnel has smaller noise than the slab track tunnel, we have suggested a new inner tunnel model to decrease the noise of the micro-pressure wave, using the ballast effect. Experimental and numerical investigations are carded out to clarify the attenuation and distortion of propagating compression wave over porous plate wall in a model tunnel. Data shows that the strength of the compression wave and a maximum pressure gradient of the compression wave was weakened. These data shows the possibility of the present alleviative method using the porous plate wall in a tunnel. 展开更多
关键词 High-speed railway tunnel Compression wave Micro-pressure wave Porous wall Alleviative method
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Refined model analysis of basement rock degradation mechanism of heavy-haul railway tunnel 被引量:1
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作者 Zheng Li Ziqiang Li +3 位作者 Ruyi Cai Yang Hua Lin Wang Dongming Gu 《Underground Space》 SCIE EI 2021年第3期342-352,共11页
This study investigated the degradation mechanism of the surrounding rock of a heavy-haul railway under a water-rich condition,based on the construction of the Taihangshan tunnel for the Wari Railway,a heavy-haul rail... This study investigated the degradation mechanism of the surrounding rock of a heavy-haul railway under a water-rich condition,based on the construction of the Taihangshan tunnel for the Wari Railway,a heavy-haul railway that used standard construction practices for axle loads of 30 t.Remote monitoring demonstrated that the coupling effect between the dynamic load of a heavy-haul train and the groundwater leads to the deterioration and hollowing of the surrounding rock.This study clarified the void evolution process and deterioration mechanism of the basement rock under the comprehensive influence of the groundwater–train dynamic load using a refined discrete element numerical simulation.The results revealed that the groundwater was the primary influencing factor in the deterioration of the lower part of the heavy-haul railway tunnel.Rock particles were gradually lost under the effects of long-term erosion due to groundwater and heavy-haul trains,which inevitably damaged the basement rock after the construction was completed.Based on this observation,the critical conditions for the deterioration and attenuation law of the physical parameters of the basement rock were obtained.The results of this study can provide ideas and serve as a reference for the forecasting and disaster treatment of basement rock damage in heavy-haul railway tunnels. 展开更多
关键词 Heavy-haul railway tunnel Refined model analysis Degradation mechanism Surrounding rock Water-rich condition
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Unsteady slipstream of a train passing through a high-speed railway tunnel with a cave 被引量:1
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作者 Xiaohui Xiong Rilong Cong +5 位作者 Xiaobai Li Yutang Geng Mingzan Tang Shujun Zhou Yanling Na Chongxu Jiang 《Transportation Safety and Environment》 EI 2022年第4期107-120,共14页
The cave is of great importance for the storage of equipment and to avoid having workers in the tunnel,but it changes the tunnel section,leads to a change of slipstream and affects the safety of trains and workers.The... The cave is of great importance for the storage of equipment and to avoid having workers in the tunnel,but it changes the tunnel section,leads to a change of slipstream and affects the safety of trains and workers.The Re-normalization group(RNG)k-εturbulence method is used to investigate the slipstream induced by a single train passing through a double-track tunnel at 350 km/h.The slipstream in a tunnel with and without a cave is compared.The slipstream components in three directions are reported comprehensively.The results show that the existence of a cave changes the slipstream at the tail of the train.At measurement points before and after the train passes the cave,the intensity of the slipstream at the tail ismitigated;as the train passes the cave,the tail slipstream is enhanced to a certain extent.With increasing lateral distance,the peak value of the slipstream with a cave decreases faster than that without a cave.These findings suggest that the presence of a cave mitigates the slipstream intensity,but special attention should be paid to the design of ancillary facilities,especially their relative location. 展开更多
关键词 High-speed train railway tunnel CAVE SLIPSTREAM
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Unsteady simulation for a high-speed train entering a tunnel 被引量:10
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作者 Xin-hua LI Jian DENG +2 位作者 Da-wei CHEN Fang-fang XIE Yao ZHENG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2011年第12期957-963,共7页
In order to study the unsteady aerodynamics effects in railway tunnels,the 3D Reynolds average Navier-Stokes equations of a viscous compressible fluid are solved,and the two-equation k-ε model is used in the simulati... In order to study the unsteady aerodynamics effects in railway tunnels,the 3D Reynolds average Navier-Stokes equations of a viscous compressible fluid are solved,and the two-equation k-ε model is used in the simulation of turbulence,while the dynamic grid technique is employed for moving bodies.We focus on obtaining the changing tendencies of the aerodynamic force of the train and the aerodynamic pressures on the tunnel wall and train surface,and discovering the relationship between the velocity of the train and the intensity of the micro pressure wave at the tunnel exit.It is shown that the amplitudes of the pressure changes in the tunnel and on the train surface are both approximately proportional to the square of the train speed,so are the microwave and the drag of the train. 展开更多
关键词 High-speed train AERODYNAMICS railway tunnel Numerical analysis
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A Study of the Weak Shock Wave Propagating over a Porous Wall/Cavity System
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作者 H.D.KIM S.J.JUNG +1 位作者 T.AOKI T.SETOGUCHI 《Journal of Thermal Science》 SCIE EI CAS CSCD 2005年第4期329-333,共5页
The present computational study addresses the attenuation of the shock wave propagating in a duct, using a porous wall/cavity system. In the present study, a weak shock wave propagating over the porous wall/cavity sys... The present computational study addresses the attenuation of the shock wave propagating in a duct, using a porous wall/cavity system. In the present study, a weak shock wave propagating over the porous wall/cavity system is investigated with computational fluid dynamics. A total variation diminishing scheme is employed to solve the unsteady, two-dimensional, compressible, Navier-Stokes equations. The Mach number of an initial shock wave is changed in the range from 1.02 to 1.12. Several different types of porous wall/cavity systems are tested to investigate the passive control effects. The results show that wall pressure strongly fluctuates due to diffraction and reflection processes of the shock waves behind the incident shock wave. From the results, it is understood that for effective alleviation of tunnel impulse waves, the length of the perforated region should be sufficiently long. 展开更多
关键词 compressible flow perforated wall railway tunnel shock wave.
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