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International conference on Sensing, Diagnostics, Prognostics, and control (SDPc)

作者： Peng Wang Zhenkai Liu Yongqiang Liu Shaopu Yang Yuqiang cai College of Mechanical Engineering North China University of Science and Technology Tangshan China School of Mechanical Engineering Shijiazhuang Tiedao University Shijiazhuang China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang China

ISBN: (数字)9798350388855

ISBN: (纸本)9798350388862

To investigate the influence of wheel wear evolution on wheel-rail contact and dynamic performance of high-speed trains, taking a high-speed train as the research object, the wheel wear tracking test was carried out to analyze the evolution law of wheel wear with the running mileage. Using the wheel-rail contact geometric relationship and non-Hertz rolling contact theory, the influence of wheel wear on wheel-rail contact geometric characteristics and contact mechanical characteristics was calculated, and the wheel-rail matching performance under wear was analyzed. The vehicle model was established by UM software, and the influence of different wheel wear treads on the vehicle's dynamic performance in a lathing cycle was investigated. The results indicate that during the evolution of wheel profile, the distribution state of wheel-rail contact points changes. With the increase of wheel tread wear, the radius difference of wheel rolling circles increases, which is conducive to improving the curve passing performance of vehicles. The wear of wheel tread leads to the increase of vehicle transmissibility and the decrease of nonlinear critical speed.

关键词： Vibrations Suspensions (mechanical systems) Stability criteria Wheels Flanges Market research Software Sensors Indexes Vehicle dynamics

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APPLIcATION AND DYNAMIcS OF MR DAMPER IN THE SEcONDARY SUSPENSION system OF HIGH SPEED TRAINS 1

APPLICATION AND DYNAMICS OF MR DAMPER IN THE SECONDARY SUSPE...

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1st International conference on mechanical system Dynamics, IcMSD 2022

作者： Zhao, Yiwei Yang, Shaopu Liu, Yongqiang Liao, Yingying Wang, Peng State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang China School of Transportation Shijiazhuang Tiedao University Shijiazhuang China School of Mechanical Engineering Shijiazhuang Tiedao University Shijiazhuang China School of Civil Engineering Shijiazhuang Tiedao University Shijiazhuang China

ISBN: (数字)9781839537837

ISBN: (纸本)9781839537837

With the increasing of the train speed, the dynamic performance of the train continues to deteriorate. Therefore, how to ensure the dynamic performance of trains including the ride comfort and stability is an important issue for engineers. In this paper, how to ensure the ride comfort of high speed trains is researched. The semi-active control technology of secondary lateral dampers is used to improve the ride comfort of the train. Firstly, a full-scale high speed train model is established by using the Universal Mechanism(UM) software, and the traditional LQR(Linear quadratic regulator) algorithm based on a 9 degrees of freedom(dof) model of high speed trains is used to calculate the active control force. Secondly, the magnetorheological(MR) damper model is used to track the control force through a tracking force controller designed in this paper, and then the MR damping force is fed back to the full-scale vehicle model to form a closed-loop system. Finally, the semi-active simulations is performed. The simulation and comparison results show that the semi-active control based on the LQR method can restrain the lateral vibration of the car body and improve the ride comfort of the train obviously. Although it deteriorates the running safety a little, it is still within the allowable range. © 2022 IET conference Proceedings. All rights reserved.

关键词： closed loop systems

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Problems and corrections of classical Mathematical Model for Piecewise Linear system

SSRN

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SSRN 2023年

作者： Shen, Yongjun Zhang, Ruiliang Han, Dong School of Mechanical Engineering Shijiazhuang Tiedao University Shijiazhuang050043 China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang050043 China

Due to the existence of gap or backlash, many mechanical systems can be simplified into piecewise linear models. The dynamic study on mechanical system should be based on reliable mathematical model, so that it is very important to determine the contact point and separation point between the primary system and the auxiliary spring system (ASS) in the piecewise linear systems. In most existing literatures on piecewise linear systems, the contact point and the separation point of the mathematical model are fixed at the gap. But in this paper, it is found that the contact point and separation point actually change with the system parameters when the ASS contains damper, which implies the most existing mathematical model are incorrect. It is firstly demonstrated through numerical solution that the primary system will prematurely separate from the ASS before reaching the gap under harmonic excitation, which shows the incorrectness of the classical mathematical model. Then, based on the mechanical model and engineering practice, two corrected mathematical models are proposed. And the motions of the primary system and ASS after prematurely separation in the corrected models are studied. Finally, through comparison of the contact point, separation point, amplitude-frequency curves and motion state between the corrected models and the classical mathematical model, it can be concluded that the corrected models are more reasonable. And the comparisons with the experimental data implies that the corrected models can better reflect the engineering practice. These results will be helpful to the study and design of the piecewise linear system. © 2023, The Authors. All rights reserved.

关键词： Piecewise linear techniques

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Subharmonic resonance of single-degree-of-freedom piecewise-smooth nonlinear oscillator

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Acta Mechanica Sinica 2020年第5期36卷 1109-1118,I0003页

作者： Jiangchuan Niu Wenjing Zhang Yongjun Shen Shaopu Yang 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

Take the single degree of freedom nonlinear oscillator with clearance under harmonic excitation as an example,the 1/3 subharmonic resonance of piecewise-smooth nonlinear oscillator is *** approximate analytical solution of 1/3 subharmonic resonance of the single-degree-of-freedom piecewise-smooth nonlinear oscillator is *** changing the solving process of Krylov-Bogoliubov-Mitropolsky(KBM)asymptotic method for subharmonic resonance of smooth nonlinear system,the classical KBM method is extended to piecewise-smooth nonlinear *** existence conditions of 1/3 subharmonic resonance steady-state solution are achieved,and the stability of the subharmonic resonance steady-statesolution is also *** is found that the clearance affects the amplitude-frequency response of subharmonic resonance in the form of equivalent negative *** a demonstration example,the accuracy of approximate analytical solution is verified by numerical solution,and they have good *** on the approximate analytical solution,the infuences of clearance on the critical frequency and amplitude-frequency response of 1/3 subharmonic resonance are analyzed in *** analysis results show that the KBM method is an effective analytical method for solving the subharmonic resonance of piecewise-smooth nonlinear *** it provides an effective reference for the study of subharmonicr esonance of other piecewise-smooth systems.

关键词： Subharmonic resonance Piecewise-smooth system Approximate analytical solution Asymptotic method

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Synergistic effect of rhamnolipid and Bacillus mucilaginosus on detoxification and activation of municipal solid waste incineration fly ash

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chemosphere 2024年 366卷 143461页

作者： Liu, Bin Sun, Shaoming Zhang, Xinyue Zhang, Shiquan Kong, Lijuan School of Materials Science and Engineering Shijiazhuang Tiedao University 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

In recent years, the substantial increase in municipal solid waste incineration fly ash (MSWIFA) production has made its treatment a critical issue. However, the high toxicity of MSWIFA makes its utilization still in the exploratory stage. In this study, the heavy metal leaching rate, particle size distribution and activity index of MSWIFA were tested to investigate the detoxification and activation effects of Bacillus mucilaginosus on MSWIFA by introducing rhamnolipid. The results show that the microbial treatment can greatly increase the leaching rate of heavy metals in MSWIFA and its 28-day and 90-day activity indexes, especially by the synergistic treatment. For the Bacillus mucilaginosus and rhamnolipid treated MSWIFA (BR-MSWIFA), the maximum leaching rates follow the order from high to low of 85.57% cr, 78% cu, 76.38% Zn, 62.78% Pb and 37.65% Mn, while having a low mass loss of less than 5%, which is important for its reuse. Moreover, compared with the untreated MSWIFA (U-MSWIFA), the average particle sizes of Bacillus mucilaginosus treated MSWIFA (B-MSWIFA) and BR-MSWIFA decrease from 8.39 μm to 7.80 μm and 4.31 μm, and the 28-day activity indexes increase from 80.19% to 101.59% and 110.61%. The effect mechanism is that rhamnolipid not only can promote the growth, reproduction, and metabolic acid production of Bacillus mucilaginosus, but also disperse the extracellular polymeric substance (EPS) and MSWIFA particles, thus increase their contact area and the bioleaching. This study provided a theoretical foundation for the harmless treatment and resource utilization of solid wastes containing heavy metals. © 2024 Elsevier Ltd

关键词： Fly ash

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An Extension of correlated Kurtosis to Tunable Q-Factor Wavelet Transform in Fault Diagnosis of Rolling Element Bearings

An Extension of Correlated Kurtosis to Tunable Q-Factor Wave...

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2021 IEEE International conference on Sensing, Diagnostics, Prognostics, and control, SDPc 2021

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

ISBN: (纸本)9781665449762

In engineering practice, the type of rolling bearing failures are typical, and the fault signals are impulsive, which are influenced by the running status, the frequency component of the vibration signals become extremely complicated. Tunable Q-Factor wavelet transform (TQWT) method based on correlation kurtosis is proposed. This method decomposes the bearing fault signal into two different parts, high and low resonance components (HRc and LRc), basing on the different characteristics of signal oscillation. Then, calculating the correlation kurtosis of each decomposition layer of LRc to achieve signal reconstruction. Envelope demodulation analysis is performed on the reconstructed LRc . This method replaces the kurtosis index used in previous studies with correlated kurtosis index, which can effectively eliminate or weaken the influence of peak value interference. Finally, the simulation signals and wheelset bearing test signals are validated. The results show that this method can extract the features of bearing outer, inner and roller under strong background noise. © 2021 IEEE.

关键词： Wavelet transforms

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Heat Transfer-Based Surface Structure Optimization of High-Speed Railway Foundation Bed in Frozen Areas

SSRN

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SSRN 2024年

作者： Qing, caolin Jie, Shaolong Yue, Zurun Mao, Shuai Zhai, Zhongang State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang050043 China College of Civil Engineering Shijiazhuang Tiedao University Shijiazhuang050043 China Shijiazhuang University Shijiazhuang050035 China

The subgrade surface deflection caused by frost heave and thawing settlement is the main cause of the deformation disease of railway subgrade in the frozen area, and its control by reducing the freezing depth is the key to ensuring the stability of train operation. This study established a subgrade temperature field model based on the measured temperature of the HQTJ-5 bid section of the Harbin–Qiqihar (Haqi) intercity railway project in china. The freezing depth of the subgrade center with the minimum monitored temperature was used as the control standard. The thermal insulation effects of different types of asphalt mixture reinforcement layers and cement-stabilized gravel subgrade surfaces on the subgrade were explored. The orthogonal test was designed, and the optimal combination of the surface structure of the foundation bed with thermal insulation and waterproof performance was derived. The results show that both asphalt mixture and cement-stabilized gravel have a thermal insulation effect, and laying on the surface layer of a subgrade bed can reduce the freezing depth. When the surface structure of the foundation bed adopted the "10 cm-thick Ac-16 c asphalt mixture reinforcement layer + 30% rubber powder cement-stabilized gravel" scheme, the thermal insulation effect was the best, and the freezing depth could be controlled within 0.5 m. Therefore, the above surface structure scheme was recommended for frozen areas, being of great significance for the prevention and treatment of frost damage deformation of the high-tech railway subgrade in the frozen area. © 2024, The Authors. All rights reserved.

关键词： Thermal conductivity

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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.

关键词：

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On the Melnikov method for fractional-order systems

arXiv

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arXiv 2024年

作者： Li, Hang Shen, Yongjun Li, Jian Dong, Jinlu Hong, Guangyang Key Laboratory of Structural Dynamics of Liaoning Province College of Sciences Northeastern University Shenyang110819 China Department of Mechanical 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 is dedicated to clarifying and introducing the correct application of Melnikov method in fractional dynamics. Attention to the complex dynamics of hyperbolic orbits and to fractional calculus can be, respectively, traced back to Poincaré’s attack on the three-body problem a century ago and to the early days of calculus three centuries ago. Nowadays, fractional calculus has been widely applied in modeling dynamic problems across various fields due to its advantages in describing problems with non-locality. Some of these models have also been confirmed to exhibit hyperbolic orbit dynamics, and recently, they have been extensively studied based on Melnikov method, an analytical approach for homoclinic and heteroclinic orbit dynamics. Despite its decade-long application in fractional dynamics, there is a universal problem in these applications that remains to be clarified, i.e., defining fractional-order systems within finite memory boundaries leads to the neglect of perturbation calculation for parts of the stable and unstable manifolds in Melnikov analysis. After clarifying and redefining the problem, a rigorous analytical case is provided for reference. Unlike existing results, the Melnikov criterion here is derived in a globally closed form, which was previously considered unobtainable due to difficulties in the analysis of fractional-order perturbations characterized by convolution integrals with power-law type singular kernels. Finally, numerical methods are employed to verify the derived Melnikov criterion. Overall, the clarification for the problem and the presented case are expected to provide insights for future research in this topic. © 2024, cc BY-Nc-ND.

关键词： Differentiation (calculus)

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A crystal-Plasticity cyclic constitutive Model for the Ratchetting of Polycrystalline Material considering Dislocation Substructures

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Acta Mechanica Solida Sinica 2020年第2期33卷 268-280页

作者： Xuehong Ren Shaopu Yang Guilin Wen Wenjie Zhao State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan UniversityChangsha 410082China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China

A crystal-plasticity cyclic constitutive model of polycrystalline material considering intra-granular heterogeneous dislocation substructures,in terms of three dislocation categories:mobile dislocations,immobile dislocations in the cell interiors and in the cell walls,is proposed based on the existing microscopic and macroscopic experimental *** multiplication,annihilation,rearrangement and immobilization of dislocations on each slip system are taken as the basic evolutionary mechanism of the three dislocation categories,and the cross-slip of screw dislocations is viewed as the dynamic recovery mechanism at room *** slip resistance associated with the isotropic hardening rule results from the interactions of dislocations on the slip ***,a modified nonlinear kinematic hardening rule and a rate-dependent flow rule at the slip system level are employed to improve the predictive capability of the model for ratchetting *** predictive ability of the developed model to uniaxial and mul-tiaxial ratchetting in macroscopic scale is verified by comparing with the experimental results of polycrystalline 316L stainless *** ratchetting in intra-granular scale which is obviously dependent on the crystallographic orientation and stress levels can be reasonably predicted by the proposed model.

关键词： Ratchetting Dislocation substructures crystal plasticity Polycrystalline materials constitutive model

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