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Erratum: ‘Scattering of SH Waves Around Circular Canyon in Inhomogeneous Wedge Space’

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Geophysical Journal International 2021年第1期226卷 345-350页

作者： Zailin Yang Xinzhu Li Yunqiu Song Guanxixi Jiang Menghan Sun Xueqian Fang College of Aerospace and Civil Engineering Harbin Engineering University Harbin China Key Laboratory of Advanced Material of Ship and Mechanics Ministry of Industry and Information Technology Harbin Engineering University Harbin China sunmenghan163@*** State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang China

Evolution Rule of Wheel Tread Wear of High-Speed train and its Influence on Dynamic Performance

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Evolution Rule of Wheel Tread Wear of High-Speed Train and i...

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

Effect of Tamping Energy on the Reinforcement of a High Embankment Filled with Soil-Rock 4

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Effect of Tamping Energy on the Reinforcement of a High Emba...

2020 4th International Conference on Water Conservancy, Hydropower and Building engineering, WCHBE 2020

作者： Hou, Licheng Yang, Guangqing Jin, Jing Lu, Huali Zhang, Ouyang Third Construction Engineering Company Ltd. China Construction Second Engineering Bureau Ltd. Beijing100070 China School of Civil Engineering Shijiazhuang Tiedao University Shijiazhuang Hebei050043 China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang Hebei050043 China School of Civil Engineering Hebei University of Science and Technology Shijiazhuang Hebei050018 China China State Construction Engineering Corp. Ltd Beijing100020 China

Through dynamic compaction tests with tamping energies of 1500, 2000, and 2500 kN•m of an embankment section in the PingShan-ZanHuang Expressway, the compression deformation behavior of the tamping settlement, soil deformation around the tamping rammer, consolidation depth, and dynamic stress of dynamic compaction were comprehensively tested. Comparative analyses of field data under three different tamping energies suggested that the optimal tamping energy, number of strikes, and vertical effective tamping depth for this embankment are 2000 kN•m, six, and 5 m, respectively. The field test data proving that dynamic compaction has a significant effect on this embankment. © Published under licence by IOP Publishing Ltd.

关键词： Embankments

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

Modeling and Simulation for Microscopic Traffic Flow Based on Comprehensive Information of The Preceding And the Following Vehicles

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SSRN 2022年

作者： Wang, Yunze Wang, Yawen Zhang, Chunbo State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang05043 China Key Laboratory of Traffic Safety and Control of Hebei Province Shijiazhuang050043 China School of Traffic and Transportation Shijiazhuang Tiedao University Shijiazhuang050043 China

A new car-following model is proposed in this study, and it considers the comprehensive information of the preceding and the following vehicles (i.e., the CIPF model) including the headway, speed difference, and acceleration. This model can be considered as a further extension of the existing forward-backward velocity difference (FBVD) model. Based on the linear stability analysis of the CIPF model, the judgment basis of the traffic flow stability is obtained. Compared with the optimal velocity (OV) model, the full velocity difference (FVD) model, and the FBVD model, the CIPF model has the largest stable region and the smallest unstable region. Using the reductive perturbation method, the nonlinear analysis of the CIPF model is performed, and the modified Korteweg-de Vries (mKdv) equation, which is used to describe the traffic flow characteristics of the system near the critical point, is obtained. Finally, the numerical simulation results show that the CIPF model can respond to the state of traffic flow better and faster than the FBVD model in vehicle start and stop simulation, and can better alleviate traffic congestion and improve the traffic flow stability in the simulation of circular road. The kink-antikink wave described by mKdV equation is simulated in the unstable region after the perturbation is added to the traffic flow, which also validates the CIPF model. © 2022, The Authors. All rights reserved.

关键词： Nonlinear analysis

Modeling and Simulation for Microscopic Traffic Flow Based on Comprehensive Information of The Preceding And the Following Vehicles

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SSRN 2022年

关键词： Nonlinear analysis

Factors Influencing Driver's Expected Psychological Vulnerability When Sharing the Road with Driverless Vehicles

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SSRN 2022年

作者： Wang, Yunze Zhao, Xuhan Zhang, Chunbo State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang050043 China Key Laboratory of Traffic Safety and Control of Hebei Province Shijiazhuang050043 China School of Traffic and Transportation Shijiazhuang Tiedao University Shijiazhuang050043 China

Few studies have examined the psychological experience of drivers of manned vehicles sharing the road with driverless vehicles. To judge whether drivers think they are in a vulnerable state and find out what makes drivers feel they will be in a state we called "expected psychological vulnerability", this paper conducted a questionnaire to collect information about the attitude, perceived usefulness, trust, perceived risk, and demographic information of drivers in a hypothetical situation involving driving on the same road as driverless vehicles. Our goal was to identify areas where the drivers felt that they would be in a "vulnerable psychological state", i.e., that they would be more vulnerable to making poor psychological judgments. The survey results indicated that 43.7 % of the respondents believed that they would be in a vulnerable state in mixed traffic competition, 30.2 % of the respondents did not know whether they would be in a vulnerable state. Further, women, people with a higher education, people with a more aggressive driving personality, older people, and those with more driving experience were more inclined to think that they would not be in a vulnerable state. Attitude, trust, and perceived usefulness all had positive impacts on judgments regarding psychological vulnerability, and perceived risk had a negative impact. Therefore, the early promotion of driverless technology should give priority to people with a higher education, more driving experience, older age, and more aggressive driving personality, and focus on attitudes towards this technology, including perceived usefulness, trust, and perceived risk. © 2022, The Authors. All rights reserved.

关键词： Vehicles

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

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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

A Numerical Study of the Aerodynamic Effect of the Ski-Suits Surface Roughness on the Ski Jumping Athlete During the Flight Phase

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SSRN 2023年

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

Surface roughness of the ski-suits can have significant effect on the aerodynamic performance of the ski jumping athlete. Herein, several typical surface roughness configurations are examined through numerical simulations. The three-dimensional athlete model is subjected to both uniformly distributed and non-uniformly distributed surface roughness. Furthermore, the athlete's model is segmented into distinct body parts to conduct a comprehensive analysis of the aerodynamic contributions from each individual segment. It is observed that the that the trunk of the athlete and the skis play predominant roles in generating aerodynamic forces during the flight phase. Additionally, the optimal surface roughness values for each part of the ski-suits are determined using a uniformly distributed model. Subsequently, these distinct optimal roughness values are combined to create a mixed, non-uniformly distributed surface roughness model, to achieve an overall optimal design of the ski-suits. Flow structures are also presented to analyse the impact of these various surface roughness conditions. It is noted that the flow suppression near the back region of the athlete body can significantly reduce the resistance force in the horizontal direction. © 2023, The Authors. All rights reserved.

关键词： Surface roughness