检索结果-内蒙古大学图书馆

SSRN 2022年

作者： Cheng, Shu-Liang Yang, Hong-Yun Yan, Qun Wang, Bin Sun, Yong-Tao Xin, Ya-Jun Ding, Qian Yan, Hao Wang, Liang Key Laboratory of Mechanical Reliability for Heavy Equipment and Large Structure of Hebei Province Yanshan University Qinhuangdao China Tianjin Key Laboratory of Soft Soils and Engineering Environment Tianjin Chengjian University Tianjin China Department of Mechanics Tianjin Key Laboratory of Nonlinear Dynamics and Control Tianjin University Tianjin China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang China Key Laboratory of Aeroacoustics and Dynamics Aircraft Strength Research Institute Xi’an China Key Laboratory of Green Construction and Intelligent Maintenance for Civil Engineering of Hebei Province Yanshan University Qinhuangdao China

In this paper, a new type of single-phase metamaterial is proposed. Based on the finite element method, the band gap characteristics of the structures with different branches are comprehensively analyzed, and the existence of the band gap is further verified by the frequency response transmission spectrum. Then, the propagation characteristics of elastic waves of different frequencies in different combinations of structures are investigated respectively. The results show that the proposed single-phase metamaterial structure has an excellent band gap range, and under the action of relatively low-frequency elastic waves, the wave propagation in the structure has a certain direction and regionality, while the elastic waves at higher frequencies are applied, the propagation direction of the wave tends to propagate in all directions. This paper provides a new idea for studying the structural design of metamaterials with specific wave propagation directions. © 2022, The Authors. All rights reserved.

关键词： Energy gap

来源：评论

学校读者我要写书评

暂无评论

Mesoscale damage analysis of UHTCC under seawater dry-wet cycles using particle flow theory

引用

Mechanics Research Communications 2025年 148卷

作者： Ruiqing Chang Zhanyou Yan Li Zhao Shuo Xu Xiya Zhao Yiqing Yan School of Traffic and Transportation Shijiazhuang Tiedao University Hebei China 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

This study investigates the effects of seawater dry-wet cycling on the dynamic compressive properties of Ultra-High Toughness Cementitious Composites (UHTCC) using a discrete element model developed with Particle Flow Code (PFC2D). Five sets of controlled laboratory dynamic compression tests with varying dry-wet cycles were conducted alongside numerical simulations to examine force chain evolution, crack propagation, and acoustic emission characteristics at the mesoscale level. Results demonstrate good agreement between numerical simulations and experimental data. The peak stress of UHTCC exhibited a non-monotonic response to increasing dry-wet cycles, initially rising before declining after reaching its maximum at 90 days. Acoustic emission events showed strong correlation with crack development, where increased crack density corresponded to higher signal intensity and event frequency. The developed discrete element model successfully captured the complete internal fracture process at microscopic scales, demonstrating its effectiveness for analyzing complex mechanical behaviors in cementitious composites.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Research on Brake Failure Control of Heavy Commercial Vehicles Based on Turning Conditions

Research on Brake Failure Control of Heavy Commercial Vehicl...

引用

Conference on Vehicle Control and Intelligence (CVCI)

作者： Yongjie Lu Fahui Wang Guangfeng Zhang State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang China

ISBN: (数字)9781728184975

ISBN: (纸本)9781728184982

With the rapid rise of the transportation industry, commercial vehicles as an important means of transportation, its safety and stability are paid more and more attention. In order to improve the safety performance of heavy commercial vehicles when braking failure occurs under turning conditions. Based on the vehicle dynamics characteristics, this paper designed the stability control strategy in the case of brake failure in the above conditions, designed a fuzzy PID controller based on yurch angular velocity control, carried out the Trucksim-Simulink joint simulation and hardware in the loop experiment to jointly verify the control effect of the brake. The results show that the influence of vehicle brake failure on vehicle driving stability is reduced, the performance of vehicle brake under long and downhill conditions and turning conditions is improved, and the safety stability of vehicle brake failure in hardware loop is improved, which meets the requirements of national standards for vehicle braking.

关键词： Stability criteria Turning Hardware safety Brakes Acceleration Standards

来源：评论

学校读者我要写书评

暂无评论

Experimental Investigations on the Wind Load Interference Effects of Single-Axis Solar Tracker Arrays

SSRN

引用

SSRN 2022年

作者： Ma, Wenyong Zhang, Weida Zhang, Xiaobin Chen, Wei Tan, Qiang School of Civil Engineering Shijiazhuang Tiedao University Hebei 050043 China Innovation Center for Wind Engineering and Wind Energy Technology of Hebei Province Hebei 050043 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 Jiangsu Guoqiang Singsun Energy Co. Ltd 213300 China

Aiming at the interference effect of wind loads on single-axis solar tracker arrays, this study conducts rigid-model pressure measurement wind tunnel tests on a single-row solar tracker and solar tracker arrays. The effects of the tilt angle and wind direction on aerodynamic characteristics are examined. The basic characteristics of the wind-induced interference effects of a single-axis solar tracker array are clarified. The results reveal that when the tilt angle is small, the interference effect is small, the tilt angle increases, the interference effect becomes stronger. From the mean pressure and torque coefficients, the interference effect is mainly manifested as a shielding effect. Based on the fluctuating pressure and torque coefficients, the interference effect appears as a shielding effect and an amplification effect in small- and large-tilt angle ranges, respectively. The wind load power spectrum of the solar modules in the rear-row of the solar tracker arrays presents remarkable frequency peaks, and experiences stronger wind-induced vibrations than the front-row modules. The influence of the wind direction results in nonuniform distributions of wind loads along the length of the solar tracker. Thus, the enhancement in wind loads on the edge areas of solar arrays caused by the wind direction should be considered. © 2022, The Authors. All rights reserved.

关键词： Wind stress

来源：评论

学校读者我要写书评

暂无评论

Effects of microstructural heterogeneity on fatigue properties of cast aluminum alloys

引用

Journal of Central South University 2020年第3期27卷 674-697页

作者： JIAO Yi-nan ZHANG Yi-fan MA Shi-qing SANG De-li ZHANG Yang ZHAO Jin-jin WU Sheng-chuan LIU Yong-qiang YANG Shao-pu School of Materials Science and Engineering Hebei Key Laboratory for Mechanics of Intelligent Materials and StructuresShijiazhuang Tiedao UniversityShijiazhuang 050043China 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 State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China State Key Laboratory of Traction Power Southwest Jiaotong UniversityChengdu 610031China

Cast Al alloys are widely employed for engine components,structural parts,gear box,chassis,*** subjected to mechanical cyclic load during *** accurate fatigue life prediction of these alloys is essential for normal operation as fatigue cracks initiated during operation induce the lubrication oil leak and serious safety *** heterogeneity,including shrinkage/gaspores and secondary phase particles,is the most detrimental factor that affects fatigue life of cast Al *** approximate fatigue life cycles could be estimated based on the size distribution and locations of shrinkage pores/*** relationship between crack population and stress was reported by statistical distributions and the cumulative probability for cast Al alloys fail at a certain stress could be predicted by combination of Paris law and pore size *** depth was found to dominate the stress field around the pore on the surface and the maximum stress increases sharply when the pore intercepted with the surface at its *** microstructure of cast Al alloys usually is composed of primary Al dendrites,eutectic silicon,Fe-rich particles and other intermetallic particles are dependent upon alloy composition and heat *** coalescence of microcracks initiated from the fractured secondary phases was clearly found and can accelerate the initiation and propagation of the fatigue cracks.A link between defect features and the fatigue strength needs to be established through a good understanding of the fatigue damage mechanisms associated with the microstructural features under specific loading *** paper reviews the influences of shrinkage/gaspores and secondary phase particles,formed during casting process,on the fatigue life of Al-Si-Mg cast Al alloys.

关键词： cast aluminum alloys fatigue microstructural heterogeneous shrinkage/gas pore secondary phase particles

来源：评论

学校读者我要写书评

暂无评论

Experimental and calculation of flexuralmechanical properties of reinforced reactive powder concrete simply supported beams

引用

Gongcheng Lixue/engineering Mechanics 2020年第6期37卷 131-139页

作者： Li, Hai-Yan Zhang, Bo-Yang Li, Jin-Shu State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University ShijiazhuangHebei050043 China Mechanics Engineering Department Shijiazhuang Tiedao University ShijiazhuangHebei050043 China

Reactive powder concrete (RPC) has superior strength, high toughness and excellent durability compared with ordinary concrete (OC). The calculation method of the strength and stiffness of components of RPC is inevitably different from ordinary concrete components. A full-scale test on the bending performance of four reinforced RPC simply supported beams is conducted. The cracking moment, ultimate bending moment and mid-span load-deformation curve of the beam are obtained. The bending deformation characteristics and failure modes of RPC simply supported beams are revealed, and the calculation formulas for the cracking moment and the bending strength of the RPC simply supported beams are derived. The ultimate compressive strain of steel fiber reinforced RPC is 4394 μΕ~5200 μΕ, and the cracking strain is 690 μΕ~820 μΕ, which are much larger than those of OC. Due to the addition of steel fibers, the influence of the tensile stress of the RPC tension zone must be considered. The derived cracking moment, the normal section bending capacity and the calculated value of the stiffness are in good agreement with the experimental values. The calculation formula has high precision and can be used for the design calculation of reinforced RPC beams. © 2020, engineering Mechanics Press. All right reserved.

关键词： Stiffness

来源：评论

学校读者我要写书评

暂无评论

Study on dynamic slaking response characteristics and calculation model of fouled ballast materials in heavy-haul railways

引用

Construction and Building Materials 2025年 481卷

作者： Yang, Zhihao Liu, Hengwen Deng, Xi Feng, Huaiping Chang, Jianmei Ma, Deliang Feng, Xiaoqing State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang050043 China School of Traffic and Transportation Shijiazhuang Tiedao University Shijiazhuang050043 China School of Civil Engineering Shijiazhuang Tiedao University Shijiazhuang050043 China

Investigating the dynamic slaking characteristics of fouled ballast is critical for elucidating the mud pumping mechanisms in heavy-haul railway ballasted track beds. In this study, in-situ fouled ballast materials from typical mud pumping sections were collected, and a series of dynamic slaking triaxial tests were conducted. The coupled effects of loading frequency, dynamic stress amplitude, and confining pressure on deformation behavior, water infiltration patterns, and moisture migration characteristics under dynamic slaking conditions were systematically examined. Moreover, the evolutionary mechanisms of softening indices in plastically creeping specimens were quantitatively analyzed, yielding computational models for both softening indices and accumulative plastic strain. Furthermore, based on the improved Iwan series model, a calculation model of the dynamic stress-strain relationship considering the load amplitude and frequency under dynamic slaking conditions was established. The dynamic slaking deformation mechanism of fouled ballast was discussed from three aspects: the hysteresis effect of dynamic slaking deformation, the critical frequency regulation mechanism, and the hydromechanical coupling and feedback laws. Based on the findings, a "frequency-amplitude" collaborative control strategy is proposed for mitigating mud pumping diseases in ballasted track beds. © 2025 Elsevier Ltd

关键词： Ballast (railroad track)

来源：评论

学校读者我要写书评

暂无评论

Stability study of electromagnetic SD oscillator vibration isolation system considering nonlinear characteristics of electromagnetic force under state feedback control

引用

Chaos, Solitons & Fractals 2025年 199卷

作者： Meiqi Wang Qian Zu Ruichen Wang Chengwei Qin Pengfei Liu School of Mechanical Engineering Shijiazhuang Tiedao University Shijiazhuang 050043 China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang 050043 China Hebei Key Laboratory of Mechanical Power and Transmission Control Shijiazhuang Tiedao University Shijiazhuang 050043 China CRRC Tangshan Co. Ltd 064000 Tangshan China

To enhance the robustness of SD oscillator system, an electromagnet with state feedback control is introduced above the oscillator, considering the nonlinear characteristics of the electromagnetic force. Initially, the system's steady-state amplitude-frequency response, phase-frequency response, and backbone curve are determined using the averaging method. These results are compared with the traditional SD oscillator, analyzing the influence of state feedback parameter on vibration isolation effectiveness and acceleration transmissibility. Subsequently, differences in bifurcation diagrams between the conventional SD oscillator and the electromagnetic SD oscillator are examined, focusing on how parameters affect the system's dynamic bifurcation characteristics. Finally, employing the cell mapping method, the global bifurcation characteristics are analyzed, investigating how parameters influence the number of attractors and the area of their attraction domains. The research indicates that the system exhibits rich nonlinear characteristics, and that appropriate selection of state feedback parameters can effectively suppress chaos and bifurcations induced by external excitation, thereby enhancing the system's stability and vibration isolation performance.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Establishment of Dynamic Model of axle Box Bearing of high-speed train under Variable Speed Conditions

Research Square

引用

Research Square 2021年

作者： Liu, Yongqiang Wang, Baosen Zhang, Bin Yang, Shaopu School of Mechanical Engineering Shijiazhuang Tiedao University Shijiazhuang050043 China School of Traffic and Transportation Shijiazhuang Tiedao University Shijiazhuang050043 China College of engineering and computing University of South Carolina ColumbiaSC29208 United States State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang050043 China

This paper establishes a dynamic model of the bearing rotor system of a high-speed train under variable speed conditions. Different from previous works, the proposed model simplifies the contact stress and considers the compensation balance excitation caused by the rotor mass eccentricity. The angle iteration method is used to solve the challenging problem that the roller space position cannot be determined in bearing rotation. The simulation results show that the model accurately describes the dynamics of bearing under varying speed profiles that contain acceleration, deceleration and speed oscillation stages. The order ratio spectrum of the bearing vibration signal indicates that both single frequency and multiple frequency in simulation results are consistent with that in theoretical results. Experiments of bearing with outer ring fault and inner ring fault under various operating conditions are presented to verify the developed model. © 2021, CC BY.

关键词： Dynamic models

来源：评论

学校读者我要写书评

暂无评论

Numerical investigation on the twisted wind-induced aeroelastic response of a square supertall building

引用

Journal of Fluids and structures 2025年 137卷

作者： Bowen YAN Qiaowen Ran Yangjin Yuan Hongyu Ren Xiao Li Xuhong Zhou Qingshan Yang Qingkuan Liu Key Laboratory of New Technology for Construction of Cities in Mountain Area (Ministry of Education) School of Civil Engineering Chongqing University Chongqing 400045 PR China Department of Civil and Environmental Engineering The Hong Kong Polytechnic University Kowloon Hung Hom Hong Kong State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang 050043 PR China

The aerodynamic and aeroelastic characteristics of a square supertall building and the surrounding wind field are numerically analyzed, accounting for the influence of the twisted wind field (TWF). A two-way coupled fluid-structure-interaction (FSI) simulation, validated by the aeroelastic experiments conducted in both TWF and conventional wind field (CWF), is employed to fulfill this purpose. This study focuses on the effect of TWF on the vortex-induced vibration (VIV) response of the building and associated aerodynamic forces acting on the aeroelastic model. The results indicate that the fluctuating forces on the tall building are reduced significantly when it is immersed in TWF compared to those in CWF. In TWF, the spectral energy of the across-wind force is dispersed over a wider frequency range than that in the CWF. Furthermore, the aeroelastic response of the building in the TWF is restricted at the upper range of the reduced wind velocity, attributed to the disordered and twisted wake flow near the building. The findings from the present study can enhance the understanding of the VIV behavior of super-tall buildings under the effect of twisted winds.

关键词：

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：