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11th International conference on Prognostics and system Health Management, PHM-Jinan 2020

作者： Liu, Wenpeng Yang, Shaopu Li, Qiang Liu, Yongqiang Beijing Jiaotong University School of Mechanical Electronic and Control Engineering Beijing China Shijiazhuang Tiedao University State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang China

ISBN: (纸本)9781728151816

Envelope analysis is one of the most advantageous methods in rolling element bearing (REB) diagnosis, but the determination of the informative frequency band (IFB) is always a huge challenge. In order to reduce the influence of discrete frequency components and strong background noise to choose IFB, a new improved Autogram is provided. Firstly, the cepstrum pre-whitening (cPW) is taken as a preprocessing method to reduce the interference from discrete frequency components in the signal. Then, the Autogram is used to decompose the pre-whitening signal and the optimal IFB is selected for a further demodulation. The simulated signals and a set of experiment signals are taken to verify its validity. The results indicates that this method can successfully address the interference generated by discrete frequency and strong background noise, and effectively extract the weak fault features of bearing. © 2020 IEEE.

关键词： Failure analysis

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Experimental study on swelling characteristics of mudstone in Baotaishan tunnel 4

Experimental study on swelling characteristics of mudstone i...

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4th International Symposium on traffic Transportation and civil Architecture, ISTTcA 2021

作者： Ding, Xiang Zhu, Yongquan Guo, Xiaolong Yun, Kai China Railway Fifth Survey and Design Institute Group Co. Ltd. Beijing102600 China Shijiazhuang Tiedao University State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Hebei Shijiazhuang050043 China School of Civil Engineering Shijiazhuang Tiedao University Hebei Shijiazhuang050043 China

ISBN: (纸本)9781665425926

In order to clarify the basic physical characteristics and swelling characteristics of mudstone along Yinlan high speed railway, the basic physical characteristics test and swelling test of mudstone were carried out based on the mudstone of Baotaishan tunnel. The test results show that: (1) the mudstone of Baotaishan tunnel is mainly composed of quartz, calcite and illite, and the content of viscous minerals is low;(2) The swelling deformation of mudstone changes with time in three typical stages: rapid growth stage, deceleration growth stage and stable stage. The mudstone swellings rapidly after encountering water, and the swelling deformation at 1h reaches more than 85% of the total deformation;(3) The swelling deformation of mudstone in Baotaishan tunnel is small, but the swelling force is 250.8kPa. The swelling load is considered in the tunnel design. The test results can provide basic data for the design and construction of swelling mudstone tunnel along Yinlan high speed railway. © 2021 IEEE.

关键词： Deformation

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Fuzzy-SMc Stabilization control Based on Vehicle-Road Recognition for Real-time and Variable Speed conditions (October 2024)

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IEEE Access 2025年

作者： Wang, Guiyang Li, Shaohua Li, Jianchao Hebei College of Industry and Technology Shijiazhuang050091 China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang050043 China

Distributed drive vehicles are able to control the output torque of each wheel independently, which can improve vehicle stability. The accuracy of road adhesion coefficient identification has a large impact on the results of yaw rate and side-slip angle estimation. A multivariate controller for real-time identification of road adhesion coefficients is designed for the Fuzzy-SMc (Fuzzy Sliding Mode control) stability-vehicle speed coupling control of yaw stability and speed tracking of distributed drive electric vehicles. The Improved LM-MMSOFNN ( Levenberg Marquardt Multi-Module Self-Organizing Neural Networks) method is utilized to realize the road adhesion coefficient identification online, fuzzy sliding mode control is used to estimate the gain of the system to eliminate uncertainties and chattering. Hierarchical control method is adopted, the upper layer calculates the additional yaw moment with vehicle longitudinal speed tracking, and the lower layer is torque distribution layer. considering motor characteristics and longitudinal force requirements, this control problem is transformed into a multi objective optimization problem. In variable speed working condition, compared with SMc control Fuzzy SMc control yaw rate curve is smoother, has less oscillation, the vehicle driving state is smoother. The value of side-slip angle is smaller the whole distance, and the maximum is 0.015deg. Thus it can be verified that the proposed method is adaptive to the real driving requirements. © 2013 IEEE.

关键词： Parameter estimation

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Effect of Deformation Twinning on Microstructure Refinement of Fe-38mn Alloy During Friction Stir Processing

SSRN

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SSRN 2022年

作者： Sang, Deli Xin, Xiaoli Fu, Ruidong Li, Yijun College of Materials Science and Engineering Shijiazhuang Tiedao University Hebei Shijiazhuang050000 China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Hebei Shijiazhuang050043 China State Key Laboratory of Metastable Materials Science and Technology Yanshan University Hebei Qinhuangdao066004 China

The effect of deformation twinning on microstructure refinement was investigated for Fe-38Mn alloy during friction stir processing. It was proved that the friction stir processing microstructure of Fe-38Mn alloy was gradient distribution. The stir zone contained both recrystallized grains and fine deformed grains with average grain size of about 15 μm, and the proportion of twin boundaries in the deformed grain zone was up to 35%. Moreover, the cyclic multidirectional shear induced micro-shear bands and sub-grains with high density dislocations, as well as plentiful deformation twins. The microstructure refinement of Fe-38Mn alloy during friction stir processing resulted from the dynamic recrystallization mechanism and twinning mechanism. In addition, the cyclic multidirectional shear deformation enhanced the deformation twinning effect, so that the microstructure refinement process was completed quickly and effectively. The above works indicate a dynamic mechanism of microstructure refinement in term of the deformation twinning during friction stir processing. © 2022, The Authors. All rights reserved.

关键词： Binary alloys

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Dynamic performance of six-axle locomotive subjected to asymmetric brake shoe forces

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Journal of central South University 2020年第9期27卷 2776-2791页

作者： LIU Peng-fei ZHANG Kai-long cAO Yun-qiang State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China School of Mechanical Engineering Shijiazhuang Tiedao UniversityShijiazhuang 050043China

To research the influence of asymmetric brake shoe forces(ABSF)induced by braking failure on the dynamic performance of six-axle locomotive,the static equilibrium model of three-axle bogie and dynamic model for locomotive are *** coupling vibration equations of axle hung motor and wheelset are *** the air braking,the influence mechanism of ABSF on the wheel-rail asymmetric motion and force characteristics are *** can be found that if the ABSF is applied in the front wheelset,all the wheelsets move laterally in the same *** the ABSF occurs in the middle or rear one,other wheelsets may move laterally towards the opposite *** motion amplitude and direction of all wheelsets strictly depend on the resultant moment of suspension yawing moment and brake shoe asymmetric *** the asymmetric braking,the free lateral gap of axle-box could increase the wheelset motion amplitude,but could not change the moving *** both the straight line and curve,the ABSF may lead to wheelset misaligning motion,intensify the wheel-rail lateral dynamic interaction and deteriorate wheel-rail contact *** for the steering wheelsets,the asymmetric braking increases the wheelset attack angle significantly,which forms the worst braking condition.

关键词： locomotive brake shoe force dynamic performance asymmetric braking wheel-rail contact

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Dynamic response analysis of the whole bridge based on vehicle-bridge coupling vibration

Dynamic response analysis of the whole bridge based on vehic...

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第八届国际振动工程会议

作者： Jing Liu Shaohua Li Jianying Ren Yu Zhang State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University School of Mechanical Engineering Shijiazhuang Tiedao University Department of Engineering Mechanics Shijiazhuang Tiedao University

In order to study the dynamic responses of the bridge under the action of vehicles, a quarter vehicle model, considering multiple points tire-road contacting and a simply supported beam is coupled to establish a vehicle-bridge interaction(VBI) model. The analytical solutions are compared with the numerical solutions of VBI responses to verify the validity of the numerical method. The dynamic responses of each cross section of the bridge are analyzed when multiple vehicles are going through the bridge at a constant speed. The global maximum values of the dynamic deflection, the dynamic bending moment and the dynamic shear force of the bridge and the corresponding position on the bridge are obtained. The effect of vehicle speed and vehicle distance on the global maximum values is further analyzed. The results show that when a critical vehicle speed is reached, the global maximum values reach the maximum. At different vehicle speeds, the global maximum dynamic deflection occurs at the points near the mid-span, the global maximum dynamic bending moment occurs at the points within 9 m on the left and right sides of the mid-span,while the global maximum dynamic shear force occurs at the bridge end. When the distance between two vehicles is larger, the global maximum values are smaller. When the distance between two vehicles is up to a critical distance, the global maximum values will no longer decrease and are the same as the maximum values when only one vehicle travels on the bridge.

关键词： VBI Dynamic response analysis of the whole bridge based on vehicle-bridge coupling vibration

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Investigation on the reinforcement effect of a bedding slope affected by a landsliding block

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Arabian Journal of Geosciences 2022年第6期15卷 1-20页

作者： Zhang, Fei Yang, Tianhong Li, Lianchong Zhu, Xinping Key Laboratory of Roads and Railway Engineering Safety Control Shijiazhuang Tiedao University Ministry of Education Shijiazhuang China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang China School of Civil Engineering Shijiazhuang Tiedao University Shijiazhuang China Center of Rock Instability and Seismicity Research School of Resources and Civil Engineering Northeastern University Shenyang Liaoning China China Coal Technology and Engineering Group Shenyang Research Institute Fushun China

The south slope of Fushun west open-pit mine located in Northeast china is a high-deep rock slope. In the last few years, a landsliding block has gradually formed in the south slope. Owing to the effect of sliding force caused by the sliding block, some damage has occurred on the foundation of Kengkou refinery which constructed in the west of the south slope. To improve the stability of the refinery foundation, three group micro-pile structures were employed to cut off the drag of the sliding block and reinforce the refinery on the southwest slope. In this study, a comprehensive method combining the microseismic monitoring technique and numerical simulation method was used, the stability of the southwest slope was evaluated, and reinforcement mechanism was deeply analyzed. A microseismic monitoring system is established on-site to obtain useful information about the damage energy, location, and magnitude of the rocks in the southwest slope. Thus, the west boundary of the landslide in the south slope of the open-pit is determined. By analyzing the numerical results, the stress concentration is discovered mainly around the micro-pile structures and near the west boundary. After reinforcement, the displacement decrease in the south-north direction is apparent. To investigate the interaction mechanism between the micro-pile and the surrounding rock mass, a local 3D numerical model is employed to help understand auxiliary information about the stress state and stress redistribution induced by failure in the surrounding rock mass. It is shown that the reinforcement effect becomes more and more evident with the increase in the number of employed micro-piles. The numerical results and in situ GPS displacement monitoring data illustrate that the micro-pile structures have an excellent strengthening result in controlling the deformation of the slope. The comprehensive methodology provides an effective way to estimate the stability and the reinforcement effect of the slope und

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Design and Analysis of the cooling Effect of the Temperature-controlled Pile (Tcp) in Permafrost Regions

SSRN

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SSRN 2022年

作者： Sun, Zhaohui Liu, Jiankun Hu, Tianfei You, Tian Fang, Jianhong School of Civil Engineering Sun Yat-sen University Southern Marine Science and Engineering Guangdong Laboratory Zhuhai519082 China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang050043 China Qinghai Research Institute of Transportation Xining810001 China

To accelerate the refreezing time of cast-in-place piles in permafrost regions and improve their long-term stability, this paper proposes a novel TcP based on solar refrigeration. The TcP consists of a solar power system (SPS), a vapor compression refrigeration system (VcRS), and a pile. Then, the cooling effect of TcP was carried out by the model test and the numerical simulation. The model test results show that both the evaporating temperature and the condensing temperature are positively correlated with the ambient temperature, but the coefficient of performance (cOP) is negatively correlated with the ambient temperature. The numerical simulation results show the TcP can significantly shorten the refreezing time. The higher the mean annual ground temperature (MGAT), the more significant the acceleration effect. With the increase in the TcP working time, the pile wall permafrost temperature tends to be stable, and the cooling radius increases continuously. The TcP can restrain the degradation rate of the permafrost table, which can be further reduced by increasing the refrigeration power and the refrigeration tube space. The tangential freezing force between the frozen soil and the pile foundation is enhanced by the cooling effect of TcP and is stronger when it is close to the middle of the pile. The TcP bearing capacity is more than 1.5 times that of a traditional pile (TP). The effect of improving the bearing capacity of the pile foundation can be achieved by increasing the refrigeration power and refrigeration tube space. Therefore, TcP can be applied to pile engineering of high-speed railways and highways in permafrost regions. © 2022, The Authors. All rights reserved.

关键词： Piles

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Effect of fractional-order PID controller with displacement feedback on the dynamics of spur gear

Effect of fractional-order PID controller with displacement ...

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第八届国际振动工程会议

作者： Jingyu Hou Shaopu Yang Qiang Li Yongqiang Liu School of Mechanical Electronic and Control Engineering Beijing Jiaotong University State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University School of Mechanical Engineering Shijiazhuang Tiedao University

A torsional vibration model of spur gear is built up with considering the effect of the time-varying mesh stiffness, backlash and static transmission error. In order to reduce and control the level of vibration, the fractional-order calculus was introduced into the traditional proportional-integral-derivative(PID) control system and the nonlinear dynamic model of gear transmission based on fractional-order PID(FOPID) controller with displacement feedback is presented. The higher-precision approximate periodic solution of this system is derived by using the incremental harmonic balance method(IHBM). Finally, the influence of the coefficients and fractional order of each link of FOPID controller with displacement feedback on the meshing vibration characteristics of the gear transmission is analyzed in detail by means of amplitude-frequency response curve. Meanwhile, the response of the system with FOPID controller is compared with that of integer-order PID controller and without PID controller. The results show that the control performance of FOPID controller is apparently better than that of integer-order PID controller. Therefore, the FOPID controller with displacement feedback is applied to investigate nonlinear behavior of gear during the meshing, which would provide a certain theoretical basis and instruction for the control of vibration and noise in the mechanical transmission.

关键词： red Effect of fractional-order PID controller with displacement feedback on the dynamics of spur gear

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Nonlinear dynamic response characteristics of SD oscillator with fractional damping

Nonlinear dynamic response characteristics of SD oscillator ...

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第八届国际振动工程会议

作者： Enli chen Minghao Wang Meiqi Wang Yujian chang State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University School of Mechanical Engineering Shijiazhuang Tiedao University School of Electrical and Electronic Engineering Shijiazhuang Tiedao University

The internal friction can be described more accurately by fractional damping than integral damping. The nonlinear dynamic response characteristics of SD oscillator with fractional damping under harmonic excitation are studied. The Fourier equivalent model is proposed to solve the nonlinear stiffness of the differential equation of system motion. The non-integrable nonlinear stiffness of the differential equation of the system is solved. The expression of amplitude-frequency response is obtained by solving the differential equation of system motion using the average method,and the stability of periodic solution is determined based on the Lyapunov stability theory and the Routh criterion. The results show the Fourier transform equivalent model of the nonlinear stiffness term of the SD oscillator can be applied to the motion characteristic of the system with large amplitude, which greatly improves the calculation accuracy. With the same damping coefficient, the amplitude-frequency response of the fractional damping system is different from that of the integral damping system, the resonance frequency and amplitude of the fractional damping system vary greatly. changing the fractional coefficient will change the amplitude-frequency response backbone curve of the fractional damping system, but the integral damping system is not affected. When the fractional order is changed, the amplitude of the fractional damping system changes opposite on both sides of the cut-off point.

关键词： SD oscillator fractional damping backbone curve nonlinear vibration

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