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Research on expansion joint for high-speed railway long-span bridges in China 认领 引用 被引量：4
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作者 Hui Guo Jinzhou Jiang +8 位作者 Suoting Hu Chun Yang Qiqi Xiang Kou Luo Xinxin Zhao Bing Li Ziquan Yan Liubin Niu Jianye Zhao 《Railway Sciences》 2025年第1期52-81,共30页
Purpose–The bridge expansion joint(BEJ)is a key device for accommodating spatial displacement at the beam end,and for providing vertical support for running trains passing over the gap between the main bridge and the... Purpose–The bridge expansion joint(BEJ)is a key device for accommodating spatial displacement at the beam end,and for providing vertical support for running trains passing over the gap between the main bridge and the approach bridge.For long-span railway bridges,it must also be coordinated with rail expansion joint(REJ),which is necessary to accommodate the expansion and contraction of,and reducing longitudinal stress in,the rails.The main aim of this study is to present analysis of recent developments in the research and application of BEJs in high-speed railway(HSR)long-span bridges in China,and to propose a performance-based integral design method for BEJs used with REJs,from both theoretical and engineering perspectives.Design/methodology/approach–The study first presents a summary on the application and maintenance of BEJs in HSR long-span bridges in China representing an overview of their state of development.Results of a survey of typical BEJ faults were analyzed,and field testing was conducted on a railway cable-stayed bridge in order to obtain information on the major mechanical characteristics of its BEJ under train load.Based on the above,a performance-based integral design method for BEJs with maximum expansion range 1600 mm(±800 mm),was proposed,covering all stages from overall conceptual design to consideration of detailed structural design issues.The performance of the novel BEJ design thus derived was then verified via theoretical analysis under different scenarios,full-scale model testing,and field testing and commissioning.Findings–Two major types of BEJs,deck-type and through-type,are used in HSR long-span bridges in China.Typical BEJ faults were found to mainly include skewness of steel sleepers at the bridge gap,abnormally large longitudinal frictional resistance,and flexural deformation of the scissor mechanisms.These faults influence BEJ functioning,and thus adversely affect track quality and train running performance at the beam end.Due to their simple and integral structure,deck-type BEJs with expansion range 1200 mm(±600 mm)or less have been favored as a solution offering improved operational conditions,and have emerged as a standard design.However,when the expansion range exceeds the above-mentioned value,special design work becomes necessary.Therefore,based on engineering practice,a performance-based integral design method for BEJs used with REJs was proposed,taking into account four major categories of performance requirements,i.e.,mechanical characteristics,train running quality,durability and insulation performance.Overall BEJ design must mainly consider component strength and the overall stiffness of BEJ;the latter factor in particular has a decisive influence on train running performance at the beam end.Detailed BEJ structural design must stress minimization of the frictional resistance of its sliding surface.The static and dynamic performance of the newlydesigned BEJ with expansion range 1600 mm have been confirmed to be satisfactory,via numerical simulation,full-scale model testing,and field testing and commissioning.Originality/value–This research provides a broad overview of the status of BEJs with large expansion range in HSR long-span bridges in China,along with novel insights into their design. 展开更多
关键词 High-speed railway(HSR) Long-span bridge Bridge expansion joint(BEJ) Integral design Rail expansion joint(REJ) Overall stiffness Longitudinal frictional resistance
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Theoretical research on structural damage alarming of long-span bridges using wavelet packet analysis 认领 引用 被引量：9
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作者 丁幼亮 李爱群 缪长青 《Journal of Southeast University(English Edition)》 EI CAS 2005年第4期459-462,共4页
The state equation and observation equation of the structural dynamic systems under various analysis scales are derived based on wavelet packet analysis. The time-frequency properties of structural dynamic response un... The state equation and observation equation of the structural dynamic systems under various analysis scales are derived based on wavelet packet analysis. The time-frequency properties of structural dynamic response under various scales are further formulated. The theoretical analysis results reveal that the wavelet packet energy spectrum （WPES） obtained from wavelet packet decomposition of structural dynamic response will detect the presence of structural damage. The sensitivity analysis of the WPES to structural damage and measurement noise is also performed. The transfer properties of the structural system matrix and the observation noise under various analysis scales are formulated, which verify the damage alarming reliability using the proposed WPES with preferable damage sensitivity and noise robusticity. 展开更多
关键词 structural damage alarming wavelet packet analysis wavelet packet energy spectrum long-span bridge
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Seismic spatial effects on long-span bridge response in nonstationary inhomogeneous random fields 认领 引用 被引量：6
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作者 林家浩 张亚辉 赵岩 《Earthquake Engineering and Engineering Vibration》 EI 2005年第1期75-82,共8页
The long-span bridge response to nonstationary multiple seismic random excitations is investigated using the PEM (pseudo excitation method). This method transforms the nonstationary random response analysis into ordin... The long-span bridge response to nonstationary multiple seismic random excitations is investigated using the PEM (pseudo excitation method). This method transforms the nonstationary random response analysis into ordinary direct dynamic analysis, and therefore, the analysis can be solved conveniently using the Newmark, Wilson-9 schemes or the precise integration method. Numerical results of the seismic response for an actual long-span bridge using the proposed PEM are given and compared with the results based on the conventional stationary analysis. From the numerical comparisons, it was found that both the seismic spatial effect and the nonstationary effect are quite important, and that both stationary and nonstationary seismic analysis should pay special attention to the wave passage effect. 展开更多
关键词 earthquake nonstationary random vibration multiple excitation long-span bridge
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Seismic spatial effects on dynamic response of long-span bridges in stationary inhomogeneous random fields 认领 引用 被引量：4
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作者 林家浩 张亚辉 赵岩 《Earthquake Engineering and Engineering Vibration》 EI 2004年第2期171-180,共10页
The seismic analysis of long-span bridges subjected to multiple ground excitations is an important problem. The conventional response spectrum method neglects the spatial effects of ground motion,and therefore may res... The seismic analysis of long-span bridges subjected to multiple ground excitations is an important problem. The conventional response spectrum method neglects the spatial effects of ground motion,and therefore may result in questionable conclusions.The random vibration approach has been regarded as more reliable.Unfortunately,so far, computational difficulties have not yet been satisfactorily resolved.In this paper,an accurate and efficient random vibration approach—pseudo excitation method (PEM),by which the above difficulties are overcome,is presented.It has been successfully used in the three dimensional seismic analysis of a number of long-span bridges with thousands of degrees of freedom and dozens of supports.The numerical results of a typical bridge show that the seismic spatial effects~ particularly the wave passage effect,are sometimes quite important in evaluating the safety of long-span bridges. 展开更多
关键词 seismic response random vibration multiple excitation long-span bridge
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A Comparative Assessment of Aerodynamic Models for Buffeting and Flutter of Long-Span Bridges 认领 引用 被引量：4
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作者 Igor Kavrakov Guido Morgenthal 《Engineering》 SCIE EI CAS 2017年第6期823-838,共16页
Wind-induced vibrations commonly represent the leading criterion in the design of long-span bridges. The aerodynamic forces in bridge aerodynamics are mainly based on the quasi-steady and linear unsteady theory. This ... Wind-induced vibrations commonly represent the leading criterion in the design of long-span bridges. The aerodynamic forces in bridge aerodynamics are mainly based on the quasi-steady and linear unsteady theory. This paper aims to investigate different formulations of self-excited and buffeting forces in the time domain by comparing the dynamic response of a multi-span cable-stayed bridge during the critical erection condition. The bridge is selected to represent a typical reference object with a bluff con- crete box girder for large river crossings. The models are viewed from a perspective of model complexity, comparing the influence of the aerodynamic properties implied in the aerodynamic models, such as aerodynamic damping and stiffness, fluid memory in the buffeting and self-excited forces, aerodynamic nonlinearity, and aerodynamic coupling on the bridge response. The selected models are studied for a windspeed range that is typical for the construction stage for two levels of turbulence intensity. Furthermore, a simplified method for the computation of buffeting forces including the aerodynamic admittance is presented, in which rational approximation is avoided. The critical flutter velocities are also compared for the selected models under laminar flow. 展开更多
关键词 Buffeting FlutterLong-span bridges Bridge aerodynamics Bridge aeroelasticity Erection stage
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Numerical simulation of aerodynamic derivatives and critical wind speed for long-span bridges based on simplified steady wind field 认领 引用
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作者 辛大波 欧进萍 《Earthquake Engineering and Engineering Vibration》 SCIE EI 2007年第2期197-203,共7页
Combining the computational fluid dynamics-based numerical simulation with the forced vibration technique for extraction of aerodynamic derivatives, an approach for calculating the aerodynamic derivatives and the crit... Combining the computational fluid dynamics-based numerical simulation with the forced vibration technique for extraction of aerodynamic derivatives, an approach for calculating the aerodynamic derivatives and the critical flutter wind speed for long-span bridges is presented in this paper. The RNG k-ε turbulent model is introduced to establish the governing equations, including the continuity equation and the Navier-Stokes equations, for solving the wind flow field around a two-dimensional bridge section. To illustrate the effectiveness and accuracy of the proposed approach, a simple application to the Hume Bridge in China is provided, and the numerical results show that the aerodynamic derivatives and the critical flutter wind speed obtained agree well with the wind tunnel test results. 展开更多
关键词 aerodynamic derivatives critical flutter wind speed numerical simulation wind tunnel test long-span bridges
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Seismic Fragility Analysis of Long-Span Bridge System with Durability Degradation 认领 引用 被引量：2
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作者 Yan Liang Jialei Yan +2 位作者 Zhanqi Cheng Huai Chen Ruimin Mao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2019年第10期177-214,共38页
An offshore long-span continuous rigid-frame bridge is taken as an example to study the effect of degradation of bond-slip behavior on the seismic performance of bridges in an offshore environment during a service per... An offshore long-span continuous rigid-frame bridge is taken as an example to study the effect of degradation of bond-slip behavior on the seismic performance of bridges in an offshore environment during a service period.On the basis of a numerical simulation analysis using the OpenSeeS platform,the influence of durability degradation of concrete carbonization,steel corrosion,and degradation of bond-slip performance is considered collectively using incremental dynamic analysis method to examine the time-varying seismic fragility of the offshore bridge.Results show that when bond slip is considered,the exceedance probability of the bridge components and the system increases significantly,and the durability degradation caused by concrete carbonization and chloride ion erosion in the whole life cycle increases the seismic response of the bridge structure.The results of the proposed time-varying seismic fragility analysis indicate that,considering the degradation of bond-slip behavior of reinforced concrete after the durability degradation of materials,the exceedance probability of the pier,bearing,abutment,and system increases with the extension of service period and the increase in seismic strength under earthquake action.In addition,with the extension of service time,the effect of bond slip on the seismic fragility of components and system gradually decreases. 展开更多
关键词 Bridge durability degradation bond slip seismic fragility
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Dynamic Deformation Monitoring for Long-Span Bridges under Construction and EMD De-noising Method 认领 引用 被引量：1
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作者 Shengxiang Huang Chao Kang Wen Zhang 《Journal of Civil Engineering and Architecture》 2016年第7期853-859,共7页
Construction progress of long-span bridge is complicated and the quality control is strict. Any disadvantage during construction may potentially affect the internal forces and deck alignments after it is open to traff... Construction progress of long-span bridge is complicated and the quality control is strict. Any disadvantage during construction may potentially affect the internal forces and deck alignments after it is open to traffic. To exactly evaluate the periodic alignments, internal forces and safety, geometrical and physical monitoring are needed during construction. This study aims at the requirement of dynamic geometric monitoring during Sutong Bridge construction, and introduces the realization and observing schemes of the self-developed GPS real-time dynamic geometrical deformation monitoring system. Affected by wind load and construction circumstance, GPS （global positioning system） monitoring signal contains a variety of noise. And the useful signal can be extracted from the signal after de-noising the noises. A de-noising method based on EMD （empirical mode decomposition） model is introduced here to process the bridge dynamic monitoring data, and with the wavelet threshold de-noising method are compared. The result shows that the EMD method has good adaptability, is free from the choice of wavelet bases and the number of decomposition layer. The method is an effective de-noising method for dynamic deformation monitoring to large-span bridges. 展开更多
关键词 Long-span bridge construction period dynamic deformation monitoring empirical mode decomposition de-noising.
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Safety of the express freight train running over a long-span bridge 认领 引用
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作者 Jingcheng Wen Yihao Qin +1 位作者 Ye Bai Xiaoqing Dong 《Railway Sciences》 2024年第4期469-479,共11页
Purpose-Express freight transportation is in rapid development currently.Owing to the higher speed of express freight train,the deformation of the bridge deck worsens the railway line condition under the action of win... Purpose-Express freight transportation is in rapid development currently.Owing to the higher speed of express freight train,the deformation of the bridge deck worsens the railway line condition under the action of wind and train moving load when the train runs over a long-span bridge.Besides,the blunt car body of vehicle has poor aerodynamic characteristics,bringing a greater challenge on the running stability in the crosswind.Design/methodology/approach-In this study,the aerodynamic force coefficients of express freight vehicles on the bridge are measured by scale model wind tunnel test.The dynamic model of the train-long-span steel truss bridge coupling system is established,and the dynamic response as well as the running safety of vehicle are evaluated.Findings-The results show that wind speed has a significant influence on running safety,which is mainly reflected in the over-limitation of wheel unloading rate.The wind speed limit decreases with train speed,and it reduces to 18.83 m/s when the train speed is 160 km/h.Originality/value-This study deepens the theoretical understanding of the interaction between vehicles and bridges and proposes new methods for analyzing similar engineering problems.It also provides a new theoretical basis for the safety assessment of express freight trains. 展开更多
关键词 Express freight train Long-span bridge Crosswind Wind tunnel test Running safety Paper type Research paper
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Multi-task multi-level alarm of long-span railway bridge monitoring systems via excitation-response indicators cross-cooperation 认领 引用
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作者 Bin Chen Jinlu Yang +1 位作者 Hanwei Zhao Mancheng Lu 《High-Speed Railway》 CSCD 2025年第4期261-266,共6页
There are multiple types of risks involved in the service of long-span railway bridges.Classical methods are difficult to provide targeted alarm information according to different situations of load anomalies and stru... There are multiple types of risks involved in the service of long-span railway bridges.Classical methods are difficult to provide targeted alarm information according to different situations of load anomalies and structural anomalies.To accurately alarm different risks of long-span railway bridges by structural health monitoring systems,this paper proposes a cross-cooperative alarm method using principal and secondary indicators during high-wind periods.It provides the prior criterion for monitoring systems under special conditions,defining the principal and secondary indicators,alarm levels,and thresholds based on the relationship between dynamic equilibrium equations and multiple linear regression analysis.Analysis of one-year monitoring data from a longspan railway cable-stayed bridge shows that the 10-min average cross-bridge wind speed(excitation indicator)can be selected as the principal indicator,while lateral displacement(response indicator)can serve as the secondary indicator.The threshold levels of the secondary indicator prioritize the safety of bridge operation(mainly aiming at the safety of trains traversing bridges),with values significantly lower than structural safety thresholds.This approach enhances alarm timeliness and effectively distinguishes between load anomalies,structural anomalies,and equipment failures.Consequently,it improves alarm accuracy and provides timely decision support for bridge maintenance,train traversing,and emergency treatment. 展开更多
关键词 Structural health monitoring Long-span bridges Special-wind events Multiple indicators Anomaly alarm
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An improved Alpha-shape algorithm for extracting section contours of the super-high steel bridge tower using point clouds 认领 引用 被引量：2
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作者 ZHANG Yiming ZHAO Tianhao +2 位作者 LIAO Ruixuan LI Haoqing WANG Hao 《Journal of Southeast University(English Edition)》 EI CAS 2026年第1期26-35,共10页
The virtual preassembly of super-high steel bridge towers faces a challenge in the efficient and precise extraction of complex cross-sectional features.Factors such as fabrication errors,gravity-induced deformations,a... The virtual preassembly of super-high steel bridge towers faces a challenge in the efficient and precise extraction of complex cross-sectional features.Factors such as fabrication errors,gravity-induced deformations,and temperature fluctuations can compromise the accuracy of contour extraction.To address these limitations,an improved Alpha-shape-based point cloud contour extraction method is proposed.The proposed approach uses a hierarchical strategy to process three-dimensional laser scanning point clouds.The processed data are then subjected to curvatureadaptive voxel filtering to reduce acquisition noise.In addition,an enhanced iterative closest point(ICP)variant with correspondence validation accurately aligns the discrete point cloud segments.The proposed curvature-responsive Alpha-shape framework enables multiscale contour delineation through topology-adaptive threshold modulation,which resolves boundary ambiguities in geometrically complex cross-sections.The method was experimentally validated using field-acquired measurement datasets from the Zhangjinggao Yangtze River Bridge tower segments,confirming its capability to reconstruct noncanonical cross-sectional geometries.Three contour extraction methods,including Poisson reconstruction,the conventional Alpha-shape algorithm,and random sample consensus with ICP(RANSAC-ICP),were compared to evaluate the performance of the proposed Alpha-shape algorithm.The results demonstrate that the proposed method achieves superior contour extraction accuracy and data reduction efficiency,highlighting its effectiveness in contour extraction tasks. 展开更多
关键词 super-high steel bridge tower point cloud contour extraction improved Alpha-shape algorithm
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Performance-based comprehensive functional damage probability assessment framework for high-speed railway bridge under earthquake 认领 引用 被引量：1
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作者 Gaoyang Zhou Zhihui Zhu +1 位作者 Weiqi Zheng Yongjiu Tang 《Railway Engineering Science》 EI 2026年第2期201-216,共16页
Current seismic damage assessments for high-speed railway(HSR)bridges primarily focus on the overall structural safety,lacking evaluations from multiple performance perspectives,which affects the post-earthquake traff... Current seismic damage assessments for high-speed railway(HSR)bridges primarily focus on the overall structural safety,lacking evaluations from multiple performance perspectives,which affects the post-earthquake traffic decision-making for the bridges.This study proposes a performance-based comprehensive functional damage probability assessment framework for high-speed railway simply supported bridges(HSRSSBs)under earthquakes.The framework categorizes the functions of HSR bridges into three levels:post-earthquake traffic function(PTF),structural bearing function(SBF),and collapse resistance function(CRF),corresponding to the operational,structural safety,and structural integrity requirements of HSRSSB,respectively.By analyzing the damage states of key bridge components during earthquakes,the functional damage probability assessment indicators and classification thresholds are established according to various performance requirements.Damage probability calculations are conducted using the probability density evolution method and vulnerability method.Finally,based on the relationship between damage probabilities at different functional levels,a comprehensive damage probability assessment framework considering the three-level performance requirements of HSRSSBs is developed,and the influence of varying pier heights on the functional damage probability relationship is examined.The results indicate that current HSRSSB designs meet all performance requirements under frequent earthquakes.Under design-level earthquake conditions,the SBF remains in a slight damage state,while the PTF exhibits varying degrees of damage,which worsens as pier height increases.The pier structure satisfies seismic demands even under rare earthquake conditions. 展开更多
关键词 Earthquake High-speed railway bridge Damage probability Functional damage Performance-based
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Solar-blind UV light-modulatedβ-Ga2O3full-wave bridge rectifier 认领 引用 被引量：2
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作者 Haifeng Chen Yuduo Zhang +9 位作者 Xiexin Sun Jingguo Zong Qin Lu Yifan Jia Zhenfu Feng Zhan Wang Lijun Li Xiangtai Liu Shaoqing Wang Yue Hao 《Journal of Semiconductors》 EI CAS CSCD 2026年第1期24-28,共5页
A monolithic integrated full-wave bridge rectifier consisted of horizontal Schottky-barrier diodes(SBD)is prepared based on 100 nm ultra-thin β-Ga2O3and demonstrated the solar-blind UV(SUV)light-modulated chara... A monolithic integrated full-wave bridge rectifier consisted of horizontal Schottky-barrier diodes(SBD)is prepared based on 100 nm ultra-thin β-Ga2O3and demonstrated the solar-blind UV(SUV)light-modulated characteristics.Under SUV light illumination,the rectifier has the excellent full-wave rectification characteristics for the AC input signals of 5,12,and 24 V with different frequencies.Further,experimental results confirmed the feasibility of continuously tuning the rectified output through SUV light-encoding.This work provides valuable insights for the development of optically programmable Ga2O3ACDC converters. 展开更多
关键词 β-Ga2O3 Schottky-barrier diode full-wave bridge rectifier solar-blind UV
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Influence study of main cable displacement-controlled device type of long-span suspension bridges on structural mechanical properties 认领 引用 被引量：2
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作者 YUAN Zhijie WANG Hao +2 位作者 MAO Jianxiao LI Rou ZONG Hai 《Journal of Southeast University(English Edition)》 EI CAS 2025年第1期27-36,共10页
Main cable displacement-controlled devices(DCDs)are key components for coordinating the vertical deformation of the main cable and main girder in the side span of continuous suspension bridges.To reveal the mechanical... Main cable displacement-controlled devices(DCDs)are key components for coordinating the vertical deformation of the main cable and main girder in the side span of continuous suspension bridges.To reveal the mechanical action mechanisms of DCD on bridge structures,a three-span continuous suspension bridge was taken as the engineering background in this study.The influence of different forms of DCD on the internal force and displacement of the components in the side span of the bridge and the structural dynamic characteristics were explored through numerical simulations.The results showed that the lack of DCD caused the main cable and main girder to have large vertical displacements.The stresses of other components were redistributed,and the safety factor of the suspenders at the side span was greatly reduced.The setting of DCD improved the vertical stiffness of the structure.The rigid DCD had larger internal forces,but its control effect on the internal forces at the side span was slightly better than that of the flexible DCD.Both forms of DCD effectively coordinated the deformation of the main cable and main girder and the stress distribution of components in the side span area.The choice of DCD form depends on the topographic factors of bridge sites and the design requirements of related components at the side span. 展开更多
关键词 long-span suspension bridge displacement-controlled device static and dynamic characteristics finite element live load
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Fragility and recoverability assessment of single-tower cable-stayed bridge under near-fault impulsive ground motion 认领 引用
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作者 Jin ZHANG Zhong-yao ZHANG Gao ZHANG 《ENGINEERING Structure and Civil Engineering》 SCIE EI CAS CSCD 2026年第4期781-803,共23页
This study examines the seismic performance and post-earthquake recoverability of cable-stayed bridges,with the Tianhekou Bridge adopted as a prototype.A refined finite element model was established,and nonlinear dyna... This study examines the seismic performance and post-earthquake recoverability of cable-stayed bridges,with the Tianhekou Bridge adopted as a prototype.A refined finite element model was established,and nonlinear dynamic analyses were performed using ground motion records from the pacific earthquake engineering research center(PEER)database.The objectives were to assess site amplification effects,compare responses under impulsive and nonimpulsive excitations,and quantify structural vulnerability and recoverability.The results show that:1)the site effects markedly amplify peak ground acceleration(PGA)and alter waveform characteristics,thereby increasing seismic demand;2)transverse displacements exceed longitudinal responses,with impulsive motions producing the largest deformations,including a maximum of 0.35 m at pier 4#;3)vulnerability analysis reveals that the probability of severe damage in bearing 2#increases with PGA,reaching 84.65%at 1.0g;and 4)recoverability assessment indicates that the bearing system has the highest restoration potential(index=0.645),while the main girder system has the lowest(index=0.282).These findings provide a basis for enhancing the seismic resilience of cable-stayed bridges. 展开更多
关键词 cable-stayed bridge site effect bridge collapse fragility analysis recoverability analysis
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Effect of weak consolidation process of liquid bridge on interparticle mechanical behavior of clathrate hydrate 认领 引用
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作者 Qiang Luo Zhi-Hui Liu +3 位作者 Xiao-Feng Dou De-Li Gao Zhi-Chao Liu Fu-Long Ning 《Petroleum Science》 SCIE EI CAS CSCD 2026年第4期1625-1635,共11页
Clarifying the mechanism that results in the mechanical behavior differences of hydrate particles in different states is of great significance for understandingthe agglomeration mechanism of hydrate particles and the ... Clarifying the mechanism that results in the mechanical behavior differences of hydrate particles in different states is of great significance for understandingthe agglomeration mechanism of hydrate particles and the mechanical behavior characteristics of the liquid bridge between particles in a pipeline environment dominated by oil or gas.In this study,the typical liquid bridge morphology and the consolidation characteristics of hydrate particles during the contact-pull process between hydrate particles and water droplets were observed using an improved micromechanical force testing device,as well as a force sensor with a higher sampling frequency and the electric displacement stage with a smaller step.It was found that the consolidation state of the liquid bridge changes in a complex manner in the gas phase environment,and there is a special weak consolidation state:when the hydrate shell on the surface of the liquid bridge is pulled off,a new hydrate shell will form on the surface of the unconverted water at the fracture until the liquid bridge is stretched to several times the particle diameter length and breaks.Based on the hydrate shell formation theory and the existing model of hydrate interparticle mechanics,a possible liquid bridge weak consolidation model was supplemented to explain this state to elucidate the mechanism that causes the difference in the mechanical behavior of the liquid bridge for hydrate particles in different states. 展开更多
关键词 Clathrate hydrate Micromechanical force test Liquid bridge Hydrate shell Consolidation
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Advancements and innovations of the construction of 600-m scale concrete arch bridges 认领 引用
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作者 Jielian ZHENG Bing TU 《ENGINEERING Structure and Civil Engineering》 SCIE EI CAS CSCD 2026年第2期263-278,共16页
In recent years,the successive completions of the Pingnan Third Bridge with an effective span of 560 m and the Tian’e Longtan Bridge with an effective span of 600 m in the Guangxi Zhuang Autonomous Region,China,signi... In recent years,the successive completions of the Pingnan Third Bridge with an effective span of 560 m and the Tian’e Longtan Bridge with an effective span of 600 m in the Guangxi Zhuang Autonomous Region,China,signify that the spanning capacity of concrete arch bridges has entered the 600-m class.This also demonstrates that concrete-filled steel tubular(CFST)arch bridges and steel-reinforced concrete(SRC)arch bridges are the two most competitive bridge-type solutions for constructing super-long arch bridges.To further summarize the construction and innovation experience of the 600-m scale concrete arch bridges,this study focuses on key computational and field-measured data from the design and construction processes of the Pingnan Third Bridge and the Tian’e Longtan Bridge.Accordingly,a detailed analysis of the similarities and differences between the two subtypes of concrete arch bridges(CFST arch bridge and SRC arch bridge)were provided,and their respective applicable conditions,span growth potential,and further optimization directions were identified.The research findings can provide valuable references for scheme selection as well as detailed design and construction of future super-long arch bridges. 展开更多
关键词 600-m scale concrete arch bridges CFST arch bridges SRC arch bridges computational and field-measured data applicable conditions span growth potential
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Acoustic characteristic optimal design for railway steel–concrete composite bridge based on the RBFNN‑NSGA‑Ⅱ algorithm 认领 引用
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作者 Yao Yuan Xiaozhen Li +4 位作者 Yifan Cheng Haonan He Zhichao Yang Xihao Jiang Di Wu 《Railway Engineering Science》 EI 2026年第2期333-348,共16页
In recent years, the issue of structure-borne noise generated by steel-concrete composite(SCC) bridges has become increasingly severe. To control this noise by adjusting the cross section parameters of SCC bridges, th... In recent years, the issue of structure-borne noise generated by steel-concrete composite(SCC) bridges has become increasingly severe. To control this noise by adjusting the cross section parameters of SCC bridges, this study first established a numerical model based on the hybrid finite element–statistical energy analysis(FE-SEA) method. The overall sound pressure levels calculated by numerical model are compared with field measurements, showing discrepancies of 0.4 dB and 1.1 dB, respectively. The comparison confirms the accuracy of the numerical model. Then, a high-accuracy radial basis function neural network(RBFNN) was trained using samples generated from the numerical model with uniform design. To achieve greater noise reduction with lower costs, the non-dominated sorting genetic algorithm(NSGA-Ⅱ) was used for multi-objective constrained optimization, resulting in the Pareto frontier for sound power levels(SWLs) and material cost. Finally, the solution set was evaluated using the technique for order preference by similarity to an ideal solution method, and the optimal combination of cross sectional parameters was obtained. This combination resulted in a 5 dB reduction in the SWL of the structure and a 23.9% reduction in material cost. 展开更多
关键词 Structure-borne noise Steel-concrete composite bridge SEA method RBFNN NSGA-II
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Dynamic behavior of track(rack)-bridge system under running vehicle and temperature load in rack railway 认领 引用
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作者 Zhihui Chen Lang Wang +2 位作者 Zhixian Chen Zhaowei Chen Jizhong Yang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2026年第1期526-536,共11页
Significant diurnal temperature variations in mountainous rack railways cause stiffness mismatches between the rack structure and simply supported bridges,leading to critical failures like bolt loosening and rack frac... Significant diurnal temperature variations in mountainous rack railways cause stiffness mismatches between the rack structure and simply supported bridges,leading to critical failures like bolt loosening and rack fractures.This study develops a dynamic model of the vehicle-rack-bridge system based on train-track-bridge interaction theory,integrating gear-rack meshing and wheel-rail contact mechanisms.The model analyzes the dynamic response of bridges with varying spans under combined thermal and dynamic loading.Numerical simulations,conducted using finite element analysis,reveal peak vibration accelerations of 1.3 m/s2for the rack,3.0 m/s2for the rail,1.2 m/s2for the sleeper,and 0.1 m/s2for the bridge,with maximum stresses of 3 MPa in the rack,8 MPa in the rail,and 25 MPa in connecting bolts.The results show significant span-dependent amplification of stress and strain in the rack system under thermo-mechanical loading,exceeding material strength limits at 60-meter spans.An innovative elastic connection method is proposed to mitigate stress concentrations effectively,en-hancing system durability.This study introduces a novel approach to modeling complex thermo-mechanical interactions in rack railway systems,validated through extensive simulations,and provides a practical solution for improving structural resilience,offering theoretical guidance for optimizing rack-bridge system design to ensure operational safety in extreme environmental conditions. 展开更多
关键词 Simply supported bridge Rack railway Bridge-track interaction Temperature loads Dynamic Mechanical
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Achieving enhancing endosome escape of Tat47-57-derived stapled peptides through decafluorobiphenyl bridge 认领 引用
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作者 Shu Li Yuanyuan Tang +4 位作者 Xiaojing Liu Shibo Song Baokang Zhu Min Chang Yali Peng 《Chinese Chemical Letters》 SCIE CAS CSCD 2026年第4期543-550,共8页
Cell-penetrating peptides(CPPs)hold great potential as a tool using non-invasive delivery of therapeutic or diagnostic molecules into mammalian cells,but their broad application has been limited by poor endosomal esca... Cell-penetrating peptides(CPPs)hold great potential as a tool using non-invasive delivery of therapeutic or diagnostic molecules into mammalian cells,but their broad application has been limited by poor endosomal escape.Thus,the rational design and selection of CPPs remains a challenge and calls for deeper mechanistic understandings.Here,we developed novel stapled cell-penetrating peptides based on the highly positively charged HIV Tat47-57 peptide using decafluorobiphenyl-cysteine SNAr chemistry which selectively disrupt endosomal membranes.A series of stapled peptides with a cross-linked structure were synthesized and investigated their cellular uptake,endosomal escape and intracellular delivery of cargoes.Among these peptides,analogues P3 and P6 demonstrated the highest cellular uptake and endosomal escape activities with efficiencies 3.5-9-fold higher than that of Tat47-57.Notably,the results demonstrated that the decafluorobiphenyl bridge of stapled peptides exhibited significant ability for cellular uptake and endosomal escape.Moreover,we found that fluorine atoms of decafluorobiphenyl bridge played a key role for disrupting endosomal membranes.Finally,the utility of this strategy has been demonstrated by the intracellular delivery of biomacromolecules(avidin and negatively charged phosphopeptides).Together,these results suggest that the decafluorobiphenyl-cysteine SNAr chemistry may be an efficient strategy for the development of novel stapled CPPs. 展开更多
关键词 Cell-penetrating peptides Endosomal escape Decafluorobiphenyl bridge Stapled peptides Intracellular delivery
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