检索结果-内蒙古大学图书馆

第八届国际振动工程会议

作者： Yu-fei Hu Xue-Qian Fang Chang-Song Zhu State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Department of Engineering Mechanics Shijiazhuang Tiedao University

The mathematical model of three-layered beams developed based on the hypothesis of the Grigolyuk–Chulkov and the nonlocal theory and the size depended equations governing the layers motions on the nano-scales is constructed. The Hamilton’s principle yields the novel equations of motion as well as the boundary/initial conditions regarding beams displacement. The latter ones clearly exhibit the size dependent dynamics of the studied nano-beams,

关键词： Chulkov and the the nonlocal theory Mathematical model of a three-layer nano-beams based on the hypotheses of the Grigolyuk

来源：评论

学校读者我要写书评

暂无评论

Experimental Study on Coupling Effects of Galloping of a Square Cylinder

Experimental Study on Coupling Effects of Galloping of a Squ...

引用

第八届国际振动工程会议

作者： Wenyong Ma Xiaobin Zhang School of Civil Engineering Shijiazhuang Tiedao University State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University

Static and elastically mounted square cylinders were tested in wind tunnel to illustrated the characteristics of galloping of a square cylinder. Aiming to reveal the coupling effect in galloping and validity of quasi-steady assumption in estimating the galloping response, aerodynamic forces in both still and vibrating cylinder are discussed. Meanwhile, the amplitudes and corresponding forces are also analyzed. The results show that the occurrence of galloping can be perfectly predicated by the static aerodynamic forces based on quasi-steady assumption. However, the aerodynamic force on vibrating cylinder illustrates significant difference because of the coupling effects. In another words, more complicated coupling effect need to be considered on estimating the aerodynamic force and galloping responses in terms of static aerodynamic forces and structural dynamics.

关键词： Experimental Study on Coupling Effects of Galloping of a Square Cylinder

来源：评论

学校读者我要写书评

暂无评论

A crystal plasticity-based constitutive model for ratchetting of cyclic hardening polycrystalline metals

引用

International Journal of Dynamics and Control 2020年第4期8卷 1161-1168页

作者： Ren, Xuehong Yang, Shaopu Zhao, Wenzhao Wen, Guilin State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan University Changsha410082 China State Key Laboratory of Mechanical Behavior in Traffic Engineering Structure and System Safety Shijiazhuang Tiedao University Shijiazhuang050043 China

A crystal plasticity-based constitutive model is developed by modifying the second item of ArmstrongFrederick (AF) nonlinear kinematic hardening rule and introducing self-hardening and latent hardening representing the dislocation interaction between slip systems. With the help of β scale-transition rule, the cyclic stressstrain responses of polycrystalline metals can be obtained from the single crystal constitutive model. Then the developed model is applied to describe the cyclic deformation behavior of a face-centered cubic polycrystalline metal, i.e., 316L stainless steel. The predicted results of the model compared with the experiments of 316L stainless steel show that the model can not only simulate the uniaxial and multiaxial ratchetting of the face-centered cubic crystal material during the asymmetrical stress-controlled cyclic loading, but also describe the cyclic hardening characteristics of materials under symmetrical strain-controlled cyclic loading. Meanwhile, the model is capable of predicting uniaxial ratchetting of different orientations at single crystal scale. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature.

关键词： Constitutive models

来源：评论

学校读者我要写书评

暂无评论

Localized space-tim e method of fundamental solutions for three-dimensional transient diffusion problem

引用

Acta Mechanica Sinica 2020年第5期36卷 1051-1057,I0002页

作者： L.Qiu J.Lin Q.-H.Qin W.Chen International Center for Simulation Software in Engineering and Sciences College of Mechanics and MaterialsHohai UniversityNanjing 210098China College of Engineering and Computer Science Australian National UniversityCanberraACT 2601Australia State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China State Key Laboratory of Acoustic Institute of AcousticsChinese Academy of SciencesBeijing 100190China

A localized space-time method of fundamental solutions(LSTMFS)is extended for solving three-dimensional transient diffusion problems in this *** interval segmentation in temporal direction is developed for the accurate simulation of long-time-dependent diffusion *** the LSTMFS,the whole space-time domain with nodes arranged i divided into a series of overlapping subdomains with a simple *** each subdomain,the conventional method of fundamental solutions is utilized and the coefficients associated with the considered domain can be explicitly *** calculating a combined sparse matrix system,the value at any node inside the space-time domain can be *** experi-ments demonstrate that high accuracy and efficiency can be simultaneously achieved via the LSTMFS,even for the problems defined on a long-time and quite complex computational domain.

关键词： Localized spacetime method of fundamental solutions Meshless method Long-time evolution Transient diffusion

来源：评论

学校读者我要写书评

暂无评论

Evaluation method and application of urban underground space networked expansion disturbance

引用

Zhejiang Daxue Xuebao (Gongxue Ban)/Journal of Zhejiang University (engineering Science) 2022年第7期56卷 1363-1374页

作者： Liu, Zhi-Chun Lei, Sheng-Xiang Li, Guo-Liang Zhang, Zhen-Bo Hu, Zhi-Nan State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang050043 China School of Civil Engineering Shijiazhuang Tiedao University Shijiazhuang050043 China China Railway Construction Limited Corporation Beijing100855 China China Railway First Survey and Design Institute Group Limited Corporation Xi’an710043 China

Five expansion pattern types and eighteen structure types were proposed, as well as the "four elements" of the expansion system based on the investigated cases of underground space expansion projects in order to evaluate the disturbance effect of urban underground space network extension construction. The total evaluation objective composed of four sub-objectives, including extensional structure, existing structure, stratum and surrounding environment, and six stress and displacement evaluation indexes were determined based on the analysis of the expansion disturbance conduction path and the internal working mechanism of its elements. The analytic hierarchy process (AHP) was used to construct the judgment matrix. The evaluation index weight was determined by expert scoring. Then the control value grading method was applied to determine the membership degree of the evaluation index, thereby constructing a five-level urban underground space network expansion disturbance classification evaluation standard. The application of the above evaluation method was conducted. The order of expansion disturbance degree of different expansion methods is expansion by small>vertical expansion>horizontal expansion >connected connection, and the order of expansion disturbance degree of different stratum is soft soil >loess >alluvial-diluvial strata>rock. The expansion disturbance degree will decrease significantly with the increase of the proximity distance for horizontal expansion. © 2022 Zhejiang University. All rights reserved.

关键词： Grading

来源：评论

学校读者我要写书评

暂无评论

The Dynamic mechanical Behavior of Sap Based Porous Cement-Based Materials Suitable for Emas

SSRN

引用

SSRN 2023年

作者： Yang, Haitao Bian, Hongjian Jing, Qingshuo Tan, Hongbo Sun, Guowen Wu, Lipeng Wang, Yichao Zhang, Zejun Wang, Wei School of Civil Engineering Shijiazhuang Tiedao University Hebei Shijiazhuang050043 China State Key Laboratory of Mechanics Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Hebei Shijiazhuang050043 China Key Laboratory of Roads and Railway Engineering Safety Control Ministry of Education Shijiazhuang Tiedao University Hebei Shijiazhuang050043 China State Key Laboratory of Silicate Materials for Architecture Wuhan University of Technology Hubei Wuhan430070 China

Superabsorbent polymers (SAP) voids have the potential to prepare cement-based materials (CBMs) that meet the engineered materials arresting system (EMAS) requirements due to their similarity to entrained air voids. This idea was validated using a crushing test and an immersion softening test in this paper. The pore structure and micromechanical properties of CBMs incorporating SAP were analyzed using an image analysis, a boiling method, a microhardness test, and a nanoindentation test. Moreover, the influence of SAP on the quasi-static and dynamic mechanical properties of CBMs was studied using a rigid press machine and an SHPB system. The results show that the crushing and immersion softening properties of CBMs can meet the EMAS requirements when SAP dosages are 10% and 12%. The optimal dosage of SAP is 10%. Under quasi-static and dynamic compression, the compressive strength and elastic modulus decrease with increasing SAP dosage, due to the growth of the total porosity of samples and the decline in the micromechanical properties of the matrix. Increasing the SAP dosage can raise the total porosity, thereby enlarging the DIF-fc value and decreasing the DIF-E value. Raising the strain rate results will enlarge the DIF-fc and DIF-E values. This is due to the growth in the damage degree of the specimen and the change in the cracking behavior under dynamic compression. © 2023, The Authors. All rights reserved.

关键词： Pore structure

来源：评论

学校读者我要写书评

暂无评论

An improved autogram and its application in bearing fault diagnosis 11

An improved autogram and its application in bearing fault di...

引用

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

来源：评论

学校读者我要写书评

暂无评论

M-T Scheme for Predicting Effective Diffusion Coefficient of Chloride Ions in Cement-based Materials

引用

Journal of Wuhan University of Technology(Materials Science) 2020年第3期35卷 520-527页

作者： SUN Guowen ZHANG Jianjian ZHANG Lijuan CAO Tongning WANG Penshuo ZHANG Ying YAN Na State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShiji-azhuang 050043China School of Materials Science and Engineering Shijiazhuang TieDao UniversityShijiazhuang 050043China Foundational Subjects Department Shijiazhuang TieDao University SiFang CollegeShijiazhuang 051132China

To investigate the transport characteristics of chloride ions in cement-based materials, the Mori-Tanaka (M-T) prediction scheme of the effective diffusion coefficient in composites containing single-phase and multi-phase inclusions is systematically deduced based on the theory of composite mechanics and porous medium. The volume fraction, morphology and distribution of aggregates, as well as the interfacial transition zone (ITZ) are fully taken into consideration in this proposed model. The results show that the algorithm of M-T prediction scheme with high accuracy is relatively simple.

关键词： M-T scheme chloride ion effective diffusion coefficient cement-based materials ITZ

来源：评论

学校读者我要写书评

暂无评论

Dynamic mechanical characteristics and anti-thaw measures of warm frozen soil

Transportation Engineering

引用

Transportation engineering 2025年 20卷

作者： Liu, Jiankun Sun, Zhaohui Cui, Yinghui Hu, Tianfei Tai, Bowen School of Civil Engineering & State Key Laboratory for Tunnel Engineering Sun Yat-Sen University Guangzhou519082 China Institute of Future Civil Engineering Sciences and Technology Chongqing Jiaotong University Chongqing 400074 China China State Railway Group Co. Ltd Beijing 100844 China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang050043 China State Key Laboratory of Cryospheric Science and Frozen Soil Engineering Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences Lanzhou730000 China

Permafrost is widely distributed across the Qinghai-Tibet Plateau, and under the influence of climate warming, low-temperature frozen soil is gradually degrading into warm frozen soil. The ratio of ice to unfrozen water in warm frozen soil is highly sensitive to temperature changes, resulting in significant instability in its mechanical properties. To ensure the long-term stability of structures overlying permafrost foundations, conducting research on the mechanical characteristics of warm frozen soil and proposing effective measures to mitigate thaw settlement are crucial. This paper presents the research progress of our team in the field of warm frozen soil dynamics. Using a dynamic triaxial apparatus for frozen soil and a self-developed dynamic direct shear apparatus, we investigated the behavior of warm frozen soil under different temperatures, revealing the influence of temperature on its dynamic stress-strain relationship and dynamic parameters. The development of frozen soil creep theory is reviewed, and advancements in frozen soil dynamics research are summarized and discussed. This paper proposes the use of solar refrigeration technology to protect permafrost, introducing a solar-powered compression refrigeration device and its working principles. The active cooling performance of the device was tested through model experiments and field trials. Additionally, the design and construction techniques of all-season cooling embankments are discussed, providing theoretical and technical support for the stability control of subgrade engineering in permafrost regions. © 2025 The Author(s)

关键词： Permafrost

来源：评论

学校读者我要写书评

暂无评论

Experimental study on swelling characteristics of mudstone in Baotaishan tunnel 4

Experimental study on swelling characteristics of mudstone i...

引用

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

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：