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Analysis of Factors Affecting Vibration Response of Axle Box Bearing of High-Speed Trains

Journal of Vibration engineering and Technologies 2025年第5期13卷 1-23页

作者： Wang, Min Yang, Shaopu Liu, Yongqiang Chen, Yanhong Zhang, Kai State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang 050043 China School of Traffic and Transportation Shijiazhuang Tiedao University Shijiazhuang 050043 China School of Mechanical Engineering Shijiazhuang Tiedao University Shijiazhuang 050043 China CRRC TANGSHAN CO. LTD Tangshan 063000 China China Water Resources Beifang Investigation Design and Research Co. Ltd. Tianjin 300222 China

During the operation of high-speed trains, the vibration characteristics of axle box bearings are influenced by multiple factors. Specifically, this paper investigates the effects of track irregularity excitation, thermal deformation, and lubrication conditions on bearing vibration response under identical working conditions. To achieve this, based on Hertzian contact theory and elastohydrodynamic lubrication principles, a dynamic model of axle box bearing for high-speed train is established. Subsequently, the validity of the proposed model is verified by the experimental data of the single wheelset rolling vibration test bench. Furthermore, the typical fault forms of bearings are simulated, and consequently their effects on bearing vibration characteristics is analyzed. Moreover, the effects of fault size, rotational speed and bearing radial clearance on the system dynamic response are studied by using the eigenvalue of the covariance matrix and root mean square (RMS) value. The results show that track irregularity greatly increases bearing vibration, thermal deformation also causes bearing vibration to intensify. On the other hand, lubrication can effectively reduce bearing vibration. Additionally, the size and location of local bearing faults, along with rotational speed and radial clearance of bearings have great influence on the eigenvalue of the covariance matrix of bearing inner ring and outer ring. Correspondingly, the RMS value of bearing vibration also varies significantly under different speeds. © Springer Nature Singapore Pte Ltd. 2025.

关键词： Bearing Lubrication Thermal deformation Track irregularity

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Determination of safety Rock Pillar Thickness in Karst Tunnel Based on Tunnel Face Displacement Mutation Criterion 11th

Determination of Safety Rock Pillar Thickness in Karst Tunne...

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11th International Conference on Civil engineering, ICCE 2024

作者： Lang, Zhijun Ma, Zecheng Li, Mangyuan Qiao, Haiyang China Construction Seventh Engineering Division Corp. Ltd. Zhengzhou 450016 China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang 050043 China School of Civil Engineering Shijiazhuang Tiedao University Shijiazhuang 050043 China

ISBN: (纸本)9783031879586

During the excavation of water-rich cave tunnels, it remains crucial to establish the safe rock pillar thickness at the excavation face to define the required reinforcement measures and guarantee operational security throughout engineering processes. Many factors, including geological conditions, the extent of karst development, and the water pressure within the karst cavity, influence the thickness of the safety rock pillar in a karst tunnel. Utilizing the displacement mutation criterion of the tunnel face, the safe rock pillar thickness for the karst tunnel is quantified through finite element modeling. The methodology commences with a test of the tunnel rock's geomechanical behavior, followed by parameter calibration for the tunnel's geological envelope. Based on the experimental correction parameters, the numerical simulation of the longitudinal deformation characteristics at the karst tunnel face is carried out, ultimately identifying the critical proximity range between solution cavities and working faces that triggers interfacial displacement instabilities. The thickness of the safe rock pillar is computationally determined through displacement mutation criterion at the tunnel face, with systematic investigation revealing the thickness of the safe rock pillar and its variation law across varying geostatic stresses and hydrostatic conditions. The results show that: (1) As submersion duration increases, the surrounding rock's cohesion and internal friction angle typically demonstrate a declining trend, resulting in reduced shear strength of the rock mass. (2) Under deeply buried conditions, the precision of the stratum structure method and its convergence limitations lead to reduced accuracy in determining safe rock pillar thickness when abrupt displacement occurs at the tunnel face, particularly when the karst cavity is positioned 1 m to 4 m from the tunnel face. (3) Integrating numerical modeling with displacement anomaly criteria enhances the accuracy of saf

关键词： Displacement Mutation Criterion Karst Tunnel Numerical Analysis Palm Face safety Rock Pillar Thickness

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Effects of Day-Night Temperature Fluctuations on Top-Down Cracking Development in Road structures

SSRN

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SSRN 2025年

作者： Li, Ting Qiao, Haoyu Xu, Peng Yang, Guangqing Faculty of Engineering University of Porto Porto4200 465 Portugal State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang050043 China

Top-down cracking has become a significant issue in road structures. Temperature is a key factor in the occurrence of top-down cracking. However, there is a lack of research on how day-night temperature fluctuations impact the propagation of top-down cracking in road structures, leading to an incomplete understanding of its development. This study employs the extended finite element method, which is an innovative approach for crack analysis, to create a simulation model of road structure with top-down cracking, integrating thermal boundary theory. The model's accuracy is confirmed through comparison with previous studies. The research then examines the temperature distribution and various influential factors, including ambient temperature, material properties, and cracking characteristics, using the stress intensity factor as the main indicator. Grey relational analysis is used to further investigate the effects of different parameters on the stress intensity factor. Additionally, the study explores the propagation path of top-down cracking in road structure under cyclic temperature loading. The findings provide new insights into the thermally-induced mechanisms behind top-down cracking development in road structures. © 2025, The Authors. All rights reserved.

关键词： Road construction

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Research on the power generation efficiency of bladeless wind turbines under different degrees of freedom based on bidirectional fluid-solid coupling

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Zhendong yu Chongji/Journal of Vibration and Shock 2025年第12期44卷 150-161页

作者： Wei, Hongwei Liu, Kan Wei, Keqin Jia, Yaya Liu, Qingkuan School of Civil Engineering Shijiazhuang Tiedao University Shijiazhuang050043 China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang050043 China Innovation Center for Wind Engineering and Wind Energy Technology of Hebei Province Shijiazhuang050043 China

A simplified model of the bladeless wind turbine was established and the formula for its power generation efficiency was derived. Numerical simulations were conducted using computational fluid dynamics software Fluent and user-defined functions (UDF), studying the vortex-induced vibration characteristics and power generation efficiency of single and dual degree-of-freedom bladeless wind turbines under different reduced wind speeds. The study shows that the difference in the degrees of freedom of the wind turbine significantly affects its vibration response, aerodynamic characteristics and power generation efficiency. The vibration amplitude initially increases and then decreases as the reduced wind speed increases, remaining stable in certain wind speed ranges. The vibration trajectory of the dual degree-of-freedom wind turbine at reduced wind speeds primarily forms a figure-eight pattern, exhibiting multi-frequency vibrations when the wind speed approaches the natural frequency, with the trajectory becoming chaotic. The power generation efficiency follows a trend of increasing first and then decreasing with the changing reduced wind speed, with the efficiency of the dual degree-of-freedom wind turbine being higher than that of the single degree-of-freedom wind turbine. At a reduced wind speed of Ur = 2. 4, the maximum power generation efficiency of the single degree-of-freedom wind turbine is 25. 19%;at Ur = 3.4, the maximum power generation efficiency of the dual degree-of-freedom wind turbine is 57. 14%. Power generation efficiency is influenced by the combined effects of incoming wind speed, vibration velocity, and lift-drag coefficients. With changes in degrees of freedom and reduced wind speeds, the wake vortex shedding patterns of the wind turbine also vary. The vortex shedding patterns of the three-dimensional bladeless wind turbine at different heights in the span direction are similar to those of the two-dimensional wind turbine, but due to smaller vortice

关键词： Energy dissipation

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The Influence of Parameter Optimization of Rubber Nodes in High-Speed Train Turning Arms on Suppressing Hunting Motion

The Influence of Parameter Optimization of Rubber Nodes in H...

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International Conference on Artificial Intelligence and Autonomous Transportation, AIAT 2024

作者： Guo, Tao Li, Ya Liu, Yongqiang Zhan Tianyou College Dalian Jiaotong University Dalian116028 China CRRC Tangshan Co. Ltd. Tangshan063000 China Shijiazhuang Enric Gas Equipment Co. Ltd. Shijiazhuang051000 China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang050043 China School of Mechanical Engineering Shijiazhuang Tiedao University Shijiazhuang050043 China

ISBN: (纸本)9789819639724

To solve the problems of frequent occurrence of lateral instability and abnormal wear of the tread surface during the service of high-speed trains, the stiffness characteristics and its parameters optimization of the rotating arm rubber node were analyzed in this paper. A high-speed train dynamic model was established using the dynamic analysis software Universal Mechanism with a type of 350 km/h high-speed train in China as the research object. Based on the mechanism of primary and secondary vehicle instability, the phenomena of abnormal hunting of the vehicle body and abnormal vibration of the bogie was reproduced through simulation, and the vehicle response and hunting characteristics were analyzed. The Poynting Thomson model, which can represent the stiffness frequency variation characteristic of rotating arm rubber node, was optimized by the genetic optimization algorithm. The research results indicate that the optimized arm node has a significant inhibitory effect on the instability of primary and secondary hunting movements. © Beijing Paike Culture Commu. Co., Ltd. 2025.

关键词： Railroad transportation

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A study on the discrete element simulation of heterogeneous asphalt under freeze–thaw cycles

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Discover Civil engineering 2025年第1期2卷 1-19页

作者： Xu, Shuo Yan, Zhanyou Zhang, Yijunjie Zhao, Li Chang, Ruiqing School of Civil Engineering Shijiazhuang Tiedao University Hebei China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Hebei China School of English Studies Tianjin Foreign Studies University Tianjin China School of Traffic and Transportation Shijiazhuang Tiedao University Hebei China

To investigate the meso-mechanical behavior of heterogeneous asphalt mixtures more effectively, a discrete element method (DEM) model was developed and used to simulate uniaxial compression tests. The Weibull distribution function was introduced into the model to characterize the heterogeneity of asphalt particle contact strength, and a nonlinear damage equation derived from linear damage theory was utilized to simulate the initial damage evolution process of the asphalt mixture. The results show that: (1) After 5, 10, and 15 freeze–thaw cycles, the peak stress of the asphalt mixture decreased by 12.2%, 18.7%, and 24.9%, respectively, while the peak strain increased by 1.92%, 6.14%, and 16.1%, consistent with experimental results. (2) Both simulation and experimental damage variable evolution diagrams exhibit an ‘S’ shape, and the Weibull function effectively expresses the heterogeneous characteristics of the asphalt mixture. (3) The shape parameter m characterizes the peak stress and brittleness of the material, while the scale parameter a characterizes its deformation capacity.

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Development and application of tail brush elastic test device

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Scientific Reports 2025年第1期15卷 1-24页

作者： Li, Jingkai Guo, Jingbo Yang, Shaopu Han, Mengze Li, Jie Zhang, Ziyue Ren, Zifeng Ge, Jun Liu, Jinbo Department of Mechanical Traffic and Transportation Shijiazhuang Tiedao University Hebei Shijiazhuang 050043 China Department of Mechanical Engineering Shijiazhuang Tiedao University Hebei Shijiazhuang 050043 China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Hebei Shijiazhuang 050043 China

The shield tail brush loss elasticity is the key reason for the failure of shield tail seal. However, due to the limitation of test equipment, there is little research on the elastic properties of tail brush. In this research, a tail brush elastic test device was developed. Through this device, the tail brush is tested for elasticity. In this test, the grease filling layer number, tail brush mass, tail clearance, pressing number and pressing time were taken as the influencing factors, and the elastic coefficient and resilience force were taken as the response values. Single-factor test was carried out for each factor, then based on the Plackett-Burmanf theory and Box-Behnken response surface design theory, the ANOVA method was used to find out the significant degree of each factor’s influence on the quantitative index. The prediction model of elastic coefficient and resilience force was fitted based on RSM theory, and the verification group was added to verify the reliability of the prediction model. The results showed that the significance of influencing factors on the elasticity coefficient was ranked as follows: tail clearance > pressing number > pressing time > grease filling layer number. The significance of influencing factors on brush resilience F was ranked as follows: tailclearance > grease filling layer number > pressing time > pressing number. The accuracy of elastic coefficient regression model is 94.1%. The accuracy of the resilience force regression model is 99.56%, and the accuracy of the prediction model is high, which can be used to predict the elasticity coefficient and resilience force. Finally, the elastoplastic development mechanism of tail brush is discussed, and the safety standard of tail brush is proposed, which provides a basis for the selection of tail brush in practical construction. © The Author(s) 2025.

关键词： Box-Behnken test Elastic coefficient Plackett-Burman test Resilience force Shield tail sealing system Tail brush

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Three-dimensional train-periodic slab track-subgrade dynamics model based on the iterative solution and Green's function method

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Computers and structures 2025年 315卷

作者： Sun, Yu Zhang, Sen Xing, Mengting Shi, Zhiyong Liu, Pengfei College of Transportation Engineering Nanjing Tech University Nanjing210009 China Key Laboratory of Mechanical Behavior Evolution and Control of Traffic Engineering Structures in Hebei Shijiazhuang Tiedao University Shijiazhuang050043 China College of Rail Transit Wuxi University Wuxi214105 China Department of Industrial Engineering University of Florence Florence50139 Italy State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang050043 China

This paper develops an iterative solution model for the efficient and accurate simulation of the dynamics of a three-dimensional (3D) train-periodic slab track-subgrade (TPSTS) system. The entire system is divided into the train-rail subsystem and the periodic slab-subgrade subsystem. An ordinary differential equation (ODE) model of the train-rail system is established, and a step-moving strategy is employed to enhance the computational efficiency. A frequency-domain Green's function method (GFM) model is employed for modelling the periodic slab-subgrade. Considering the periodicity, symmetry, and attenuation characteristics of the track structure, the Green's function of the slab-subgrade structure is obtained by conducting harmonic response analysis on a finite element model (FEM) of a quarter slab-subgrade structure. The proposed model is utilized to investigate the vibration characteristics of the high-speed train-track-subgrade system. The results indicate that the model exhibits good convergence, accuracy, and efficiency. The periodicity of the track structure has a significant impact on the statistical values of subgrade displacement and stress amplitudes along the track's longitudinal direction. At the subgrade surface, the amplitudes of displacement, stress, and acceleration exhibit fluctuations in the lateral direction of the track. However, with increasing depth, these amplitudes generally attenuate, leading to a more uniform distribution. © 2025 Elsevier Ltd

关键词： Railroad transportation

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Optimal Design and Seismic Performance of Base-Isolated structures with Varying Heights Equipped with Tuned Inerter Dampers Subjected to Far-Fault and Near-Fault Ground Motions

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Applied Sciences (Switzerland) 2025年第9期15卷 4739-4739页

作者： Kang, Yingjie Zhang, Zewen Zhang, Zeyu Zhang, Xinyu Liu, Qingkuan Key Laboratory of Roads and Railway Engineering Safety Control Shijiazhuang Tiedao University Ministry of Education Shijiazhuang050043 China Innovation Center for Wind Engineering and Wind Energy Technology of Hebei Province Shijiazhuang050043 China School of Civil Engineering Shijiazhuang Tiedao University Shijiazhuang050043 China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang050043 China

This paper investigates the optimal design of base-isolated structures equipped with tuned inerter dampers (TIDs) subjected to various ground motions. The Clough–Penzien model is employed to simulate the power spectrum of three types of ground motions: far-fault, near-fault without pulse subset, and near-fault with pulse subset, with the relevant parameters identified based on actual ground motions. The optimal parameters of the TID for base-isolated structures are determined using the H2 optimization criterion to reduce the structural displacement response. The impact of relevant design properties about the optimal parameters is analyzed. The seismic control effectiveness of the TID for 5-storey, 10-storey, and 15-storey base-isolated structures with varying heights is then evaluated through time history analysis, considering far-fault, near-fault without pulse subset, and near-fault with pulse subset ground motions. The main conclusions of this study are as follows: the ground motion type, the natural vibration period of the isolated structure, the damping ratio of the isolated structure and the mass ratio of the TID all affect the optimal parameters and should be analyzed based on specific circumstances. The control effectiveness of the TID on displacement and acceleration response is more pronounced under far-fault ground motion than under near-fault ground motion. The TID equipped in the isolation storey exhibits considerable effectiveness in controlling the seismic response of 5-storey and 10-storey base isolated structures, while it exhibits weaker control over the seismic response of the 15-storey structure. Additionally, while the TID primarily targets displacement response control, it also exhibits substantial control over the absolute acceleration response of the structure. © 2025 by the authors.

关键词： Seismic design

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Negative-pressure soft pneumatic actuators enabled by asymmetrically distributed bending units

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Extreme Mechanics Letters 2025年 77卷

作者： Fu, Zeyu Chen, Tianyu Zou, Haoran Zhu, Zhiwei Deng, Zichen Wang, Yifan School of Mechanics Civil Engineering and Architecture Northwestern Polytechnical University Xi'an710072 China MIIT Key Laboratory of Dynamics and Control of Complex Systems Northwestern Polytechnical University Xi'an710072 China School of Mechanical and Aerospace Engineering Nanyang Technological University Singapore 639798 Singapore State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang050043 China

Soft pneumatic actuators are highly flexible and can adapt to complex environments, attracting significant attention for their ability to operate in settings where rigid actuators cannot. Most existing soft pneumatic actuators are powered by positive pressure, which has the disadvantage of volume increase during operation and risk of exploding under large pressures. In this study, we designed a new type of soft actuator by inducing asymmetric bending deformation throughout a holey structure under negative pressure. Using finite element analysis and a theoretical model, we studied the effects of various geometric parameters on the structure's bending behavior. We found that the displacement of the circle's center from the central axis is a parameter with the most significant impact on the bending behavior of the structure. By designing circular holes with offset from the central axis, the structure can bend toward the offset direction during subsequent bending deformation. Based on this deformation mechanism, we designed a soft gripper that bends upon actuation and effectively picks up objects. We further designed a bi-directional gripper that bends towards both sides and a circular gripper that contracts towards the center upon evacuation to hold objects. These soft grippers’ grasping capabilities are validated by experimental tests. Finally, by arranging the holes in a wavy pattern within the structure, we created a crawling robot that moves forward through cyclic negative pressure actuation. These findings highlight the potential of leveraging bending behaviors in asymmetrically distributed holey structures for the development of negative-pressure driven soft actuators and robots. © 2025 Elsevier Ltd

关键词： Pneumatic actuators

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