首页 > 最新文献

Shock and Vibration最新文献

英文 中文
Investigations of Dynamic Mechanical Performance of Rubber Concrete under Freeze-Thaw Cycle Damage 冻融循环损伤下橡胶混凝土动态力学性能研究
4区 工程技术 Q3 ACOUSTICS Pub Date : 2023-10-25 DOI: 10.1155/2023/6621439
Jingli Zhang
In order to study the effect of the freeze-thaw cycle on the integrity and dynamic mechanical performance of rubber concrete, the wave speed of rubber concrete specimens with 10% rubber volume was measured by a nonmetallic ultrasonic detector. The impact tests were also performed on rubber concrete specimens with different numbers of freeze-thaw cycles (0, 25, 50, 75, 100, and 125) at different impact air pressures (0.3, 0.4, 0.5, and 0.6 MPa) using a 74 mm diameter split Hopkinson pressure bar (SHPB) device, peak stress, ultimate strain dynamic intensity enhancement factor (DIF), and energy absorption effect. The results show that with the increase of freeze-thaw cycles, the wave speed decreases, and the freeze-thaw action will damage the rubber concrete and reduce the longitudinal wave velocity. Under the same freeze-thaw cycles, with the rise of strain rate, the peak stress, limit strain, DIF, and absorbed energy increase, and there is an obvious strain rate effect; under the pressure of 0.6 MPa, the peak stress of 25, 50, 75, 100, and 125 freeze-thaw cycles decreases by 25.1%, 37.1%, 46%, 52.5%, and 54.8%. With the increase of the freeze-thaw cycles, the peak stress of the specimen decreases, and the decrease gradually decreases. After the number of cycles exceeds 100, the stress decrease of the specimen is no longer obvious, the limit strain increases, and the absorbed energy decreases. The freeze-thaw environment significantly reduces the strength and integrity of rubber concrete specimens.
为了研究冻融循环对橡胶混凝土完整性和动态力学性能的影响,采用非金属超声探测仪测量了橡胶体积为10%的橡胶混凝土试件的波速。采用直径74 mm的劈裂式霍普金森压杆(SHPB)装置、峰值应力、极限应变动强度增强因子(DIF)和能量吸收效应,对不同冻融循环次数(0、25、50、75、100和125)的橡胶混凝土试件在不同冲击气压(0.3、0.4、0.5和0.6 MPa)下进行冲击试验。结果表明:随着冻融循环次数的增加,波浪速度减小,冻融作用会破坏橡胶混凝土,使纵波速度降低;在相同冻融循环次数下,随着应变速率的升高,峰值应力、极限应变、DIF和吸收能量均增大,且存在明显的应变速率效应;在0.6 MPa压力下,25、50、75、100和125次冻融循环的峰值应力分别降低了25.1%、37.1%、46%、52.5%和54.8%。随着冻融循环次数的增加,试件的峰值应力减小,且减小幅度逐渐减小。循环次数超过100次后,试样的应力下降不再明显,极限应变增大,吸收能减小。冻融环境显著降低了橡胶混凝土试件的强度和完整性。
{"title":"Investigations of Dynamic Mechanical Performance of Rubber Concrete under Freeze-Thaw Cycle Damage","authors":"Jingli Zhang","doi":"10.1155/2023/6621439","DOIUrl":"https://doi.org/10.1155/2023/6621439","url":null,"abstract":"In order to study the effect of the freeze-thaw cycle on the integrity and dynamic mechanical performance of rubber concrete, the wave speed of rubber concrete specimens with 10% rubber volume was measured by a nonmetallic ultrasonic detector. The impact tests were also performed on rubber concrete specimens with different numbers of freeze-thaw cycles (0, 25, 50, 75, 100, and 125) at different impact air pressures (0.3, 0.4, 0.5, and 0.6 MPa) using a 74 mm diameter split Hopkinson pressure bar (SHPB) device, peak stress, ultimate strain dynamic intensity enhancement factor (DIF), and energy absorption effect. The results show that with the increase of freeze-thaw cycles, the wave speed decreases, and the freeze-thaw action will damage the rubber concrete and reduce the longitudinal wave velocity. Under the same freeze-thaw cycles, with the rise of strain rate, the peak stress, limit strain, DIF, and absorbed energy increase, and there is an obvious strain rate effect; under the pressure of 0.6 MPa, the peak stress of 25, 50, 75, 100, and 125 freeze-thaw cycles decreases by 25.1%, 37.1%, 46%, 52.5%, and 54.8%. With the increase of the freeze-thaw cycles, the peak stress of the specimen decreases, and the decrease gradually decreases. After the number of cycles exceeds 100, the stress decrease of the specimen is no longer obvious, the limit strain increases, and the absorbed energy decreases. The freeze-thaw environment significantly reduces the strength and integrity of rubber concrete specimens.","PeriodicalId":21915,"journal":{"name":"Shock and Vibration","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135169624","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Suppressing Milling Chatter of Thin-Walled Parts by Eddy Current Dampers 用涡流阻尼器抑制薄壁零件的铣削颤振
4区 工程技术 Q3 ACOUSTICS Pub Date : 2023-10-25 DOI: 10.1155/2023/9533689
Junming Hou, Baosheng Wang, Hongyan Hao
Machining vibrations often occur when working with thin-walled workpieces. One effective method to mitigate these vibrations is by using a damper, which can enhance machining accuracy, surface finish, and tool life. However, traditional contact dampers have a drawback in that they require direct contact with the workpiece, leading to friction, wear, increased cutting forces, and reduced machining accuracy. In contrast, electromagnetic eddy current dampers are noncontact dampers that can effectively suppress machining vibrations without the need for physical contact. In this study, a method to suppress machining vibrations in thin-walled workpieces using electromagnetic eddy current dampers is proposed. By establishing a theoretical model for the electromagnetic damper, the damping force and equivalent damping of the damper are determined. Subsequently, the impact of electromagnetic dampers on frequency response functions and machining vibrations are investigated through hammer impact tests. The results indicate that increasing the surface damper voltage and reducing the air gap both enhance the equivalent damping of the electromagnetic eddy current damper. Moreover, cutting experiments are conducted to analyze the surface roughness of thin-walled workpieces with and without dampers. The results demonstrate that the eddy current damper can effectively increase the equivalent damping and provide the necessary damping force to suppress machining chatter. Overall, the proposed method utilizing electromagnetic eddy current dampers presents a promising solution for suppressing machining vibrations in thin-walled workpieces.
加工薄壁工件时经常发生加工振动。减轻这些振动的一种有效方法是使用阻尼器,这可以提高加工精度,表面光洁度和刀具寿命。然而,传统的接触阻尼器有一个缺点,即它们需要与工件直接接触,导致摩擦、磨损、切削力增加和加工精度降低。相比之下,电磁涡流阻尼器是非接触式阻尼器,无需物理接触即可有效抑制加工振动。提出了一种利用电磁涡流阻尼器抑制薄壁工件加工振动的方法。通过建立电磁阻尼器的理论模型,确定了电磁阻尼器的阻尼力和等效阻尼。随后,通过锤击试验研究了电磁阻尼器对频率响应函数和加工振动的影响。结果表明,增大表面阻尼器电压和减小气隙均能提高电磁涡流阻尼器的等效阻尼。通过切削实验分析了带阻尼器和不带阻尼器薄壁工件的表面粗糙度。结果表明,涡流阻尼器可以有效地增加等效阻尼,并提供必要的阻尼力来抑制加工颤振。总的来说,利用电磁涡流阻尼器的方法为抑制薄壁工件的加工振动提供了一种有前途的解决方案。
{"title":"Suppressing Milling Chatter of Thin-Walled Parts by Eddy Current Dampers","authors":"Junming Hou, Baosheng Wang, Hongyan Hao","doi":"10.1155/2023/9533689","DOIUrl":"https://doi.org/10.1155/2023/9533689","url":null,"abstract":"Machining vibrations often occur when working with thin-walled workpieces. One effective method to mitigate these vibrations is by using a damper, which can enhance machining accuracy, surface finish, and tool life. However, traditional contact dampers have a drawback in that they require direct contact with the workpiece, leading to friction, wear, increased cutting forces, and reduced machining accuracy. In contrast, electromagnetic eddy current dampers are noncontact dampers that can effectively suppress machining vibrations without the need for physical contact. In this study, a method to suppress machining vibrations in thin-walled workpieces using electromagnetic eddy current dampers is proposed. By establishing a theoretical model for the electromagnetic damper, the damping force and equivalent damping of the damper are determined. Subsequently, the impact of electromagnetic dampers on frequency response functions and machining vibrations are investigated through hammer impact tests. The results indicate that increasing the surface damper voltage and reducing the air gap both enhance the equivalent damping of the electromagnetic eddy current damper. Moreover, cutting experiments are conducted to analyze the surface roughness of thin-walled workpieces with and without dampers. The results demonstrate that the eddy current damper can effectively increase the equivalent damping and provide the necessary damping force to suppress machining chatter. Overall, the proposed method utilizing electromagnetic eddy current dampers presents a promising solution for suppressing machining vibrations in thin-walled workpieces.","PeriodicalId":21915,"journal":{"name":"Shock and Vibration","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135217142","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Retracted: Mining Stress Distribution in Stope and Overlying Rock Fracture Characteristics and Its Disaster-Pregnant Mechanism of Coal Mine Earthquake 煤矿地震采场采动应力分布及上覆岩断裂特征及其孕灾机制
4区 工程技术 Q3 ACOUSTICS Pub Date : 2023-10-18 DOI: 10.1155/2023/9813172
Shock and Vibration
{"title":"Retracted: Mining Stress Distribution in Stope and Overlying Rock Fracture Characteristics and Its Disaster-Pregnant Mechanism of Coal Mine Earthquake","authors":"Shock and Vibration","doi":"10.1155/2023/9813172","DOIUrl":"https://doi.org/10.1155/2023/9813172","url":null,"abstract":"<jats:p />","PeriodicalId":21915,"journal":{"name":"Shock and Vibration","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135823587","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Retracted: Research on Quality Anomaly Recognition Method Based on Optimized Probabilistic Neural Network 基于优化概率神经网络的质量异常识别方法研究
4区 工程技术 Q3 ACOUSTICS Pub Date : 2023-10-18 DOI: 10.1155/2023/9795858
Shock and Vibration
{"title":"Retracted: Research on Quality Anomaly Recognition Method Based on Optimized Probabilistic Neural Network","authors":"Shock and Vibration","doi":"10.1155/2023/9795858","DOIUrl":"https://doi.org/10.1155/2023/9795858","url":null,"abstract":"<jats:p />","PeriodicalId":21915,"journal":{"name":"Shock and Vibration","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135824501","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Deformation Characteristics of a Deep Subway Foundation Pit in Hard Rock Strata under a Delayed Supporting Condition 延迟支护条件下地铁硬岩深基坑变形特性研究
4区 工程技术 Q3 ACOUSTICS Pub Date : 2023-10-12 DOI: 10.1155/2023/5155504
Yang Li, Zhanguo Ma, Furong Gao, Peng Gong, Zhiqun Gong, Kelong Li
In this investigation, deformations of a deep foundation pit in hard rock strata, respectively, under delayed and in-time supporting schemes of one-layer transverse reinforced concrete bracings at the top of the foundation pit, one-layer steel bracings at a depth of 8 m, and one-layer prestressed anchorages at a depth of 22.5 m during excavation were characterized according to lateral deformations of the foundation pit, settlements of the surrounding ground, and axial forces of the steel bracings according to numerical calculations and on-site monitoring. Numerical calculation results showed that the maximum lateral deformations of the foundation pit and settlements of the surrounding ground were, respectively, 10.34 mm and 8.49 mm at an excavation depth of 31 m, which were obviously larger than those under in-time supporting. Meanwhile, under delayed supporting conditions, lateral deformations of the foundation pit and settlements of the surrounding ground were far less than the allowed values, respectively, being 0.3% and 0.15% of the excavation depth, required in the Chinese standard of GB50007-2011, indicating that the foundation pit under delayed supporting conditions had good stability. Therefore, when excavating deep foundation pits in hard rock strata, proper delayed supporting schemes could be considered so that strengths of the surrounding hard rocks could be utilized to the fullest, and at the same time, more spaces for excavation could be freed up, and construction duration and construction costs could thus be lowered.
本研究根据基坑侧向变形、周围地面沉降、开挖过程中,对某硬岩层深基坑在基坑顶部一层横向钢筋混凝土支撑、8 m深度一层钢支撑和22.5 m深度一层预应力锚杆的延迟支护方案和及时支护方案下的变形进行了表征。并根据数值计算和现场监测对钢支撑的轴向力进行了计算。数值计算结果表明,在开挖深度为31 m时,基坑最大侧向变形量为10.34 mm,周围地面沉降量为8.49 mm,明显大于支护时的侧向变形量。同时,在延迟支护条件下,基坑侧向变形和周围地面沉降均远小于中国GB50007-2011标准开挖深度的0.3%和0.15%允准值,表明延迟支护条件下的基坑具有较好的稳定性。因此,在硬岩层中开挖深基坑时,可以考虑适当的延期支护方案,充分发挥周围硬岩层的强度,同时可以腾出更多的开挖空间,降低施工工期和施工成本。
{"title":"Deformation Characteristics of a Deep Subway Foundation Pit in Hard Rock Strata under a Delayed Supporting Condition","authors":"Yang Li, Zhanguo Ma, Furong Gao, Peng Gong, Zhiqun Gong, Kelong Li","doi":"10.1155/2023/5155504","DOIUrl":"https://doi.org/10.1155/2023/5155504","url":null,"abstract":"In this investigation, deformations of a deep foundation pit in hard rock strata, respectively, under delayed and in-time supporting schemes of one-layer transverse reinforced concrete bracings at the top of the foundation pit, one-layer steel bracings at a depth of 8 m, and one-layer prestressed anchorages at a depth of 22.5 m during excavation were characterized according to lateral deformations of the foundation pit, settlements of the surrounding ground, and axial forces of the steel bracings according to numerical calculations and on-site monitoring. Numerical calculation results showed that the maximum lateral deformations of the foundation pit and settlements of the surrounding ground were, respectively, 10.34 mm and 8.49 mm at an excavation depth of 31 m, which were obviously larger than those under in-time supporting. Meanwhile, under delayed supporting conditions, lateral deformations of the foundation pit and settlements of the surrounding ground were far less than the allowed values, respectively, being 0.3% and 0.15% of the excavation depth, required in the Chinese standard of GB50007-2011, indicating that the foundation pit under delayed supporting conditions had good stability. Therefore, when excavating deep foundation pits in hard rock strata, proper delayed supporting schemes could be considered so that strengths of the surrounding hard rocks could be utilized to the fullest, and at the same time, more spaces for excavation could be freed up, and construction duration and construction costs could thus be lowered.","PeriodicalId":21915,"journal":{"name":"Shock and Vibration","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135967641","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Fractional Order Derivative and Time-Delay Feedback Enabled Stochastic Resonance for Bearing Fault Diagnosis 基于分数阶导数和时滞反馈的随机共振轴承故障诊断
4区 工程技术 Q3 ACOUSTICS Pub Date : 2023-10-10 DOI: 10.1155/2023/9950270
Yidan Mei, Lutie Chen, Wentao Xu, Chao Liu, Zijian Qiao, Zhihui Lai
The benefits of noise can be found in nonlinear systems where a type of resonances can inject the noise into systems to enhance weak signals of interest, including stochastic resonance, vibrational resonance, and chaotic resonance. Such benefits of noise can be improved further by adding some items into the nonlinear systems. Considering the time-dependent memory of fractional-order derivative and time-delay feedback which makes the nonlinear systems take advantage of their historical information and makes the output of nonlinear systems affect the input by feedback control, therefore, we attempt to design the model of stochastic resonance (SR) enhanced by both fractional-order derivative and time-delay feedback. Among them, fractional-order derivative and time delay would reinforce the memory of nonlinear systems for historical information and feedback would use the output of systems to control the systems precisely. Therefore, we hope that their advantages would be fused to improve the weak signal detection performance of SR further. Then, it would be applied to bearing fault diagnosis and compared with that without fractional-order derivative and time-delay feedback and even other diagnostic methods. The experimental results indicate that the SR enhanced by fractional-order derivative and time-delay feedback where a local signal-to-noise ratio is designed as the objective function to optimize these tuning parameters of the proposed method could enhance early fault signature of bearings and outperform that without fractional-order derivative and time-delay feedback and even infogram method.
噪声的好处可以在非线性系统中发现,其中一种共振可以将噪声注入系统以增强感兴趣的弱信号,包括随机共振、振动共振和混沌共振。通过在非线性系统中添加一些元素,可以进一步改善噪声的这些好处。考虑到分数阶导数和时滞反馈的时变记忆使得非线性系统利用其历史信息,并通过反馈控制使非线性系统的输出影响输入,因此,我们尝试设计分数阶导数和时滞反馈共同增强的随机共振(SR)模型。其中,分数阶导数和时滞会增强非线性系统对历史信息的记忆,反馈会利用系统的输出来精确控制系统。因此,我们希望融合它们的优点,进一步提高SR的微弱信号检测性能。然后将其应用于轴承故障诊断,并与不含分数阶导数和时滞反馈等诊断方法的诊断结果进行比较。实验结果表明,以局部信噪比为优化目标函数的分数阶导数和时滞反馈增强的SR能增强轴承的早期故障特征,优于没有分数阶导数和时滞反馈甚至信息图的方法。
{"title":"Fractional Order Derivative and Time-Delay Feedback Enabled Stochastic Resonance for Bearing Fault Diagnosis","authors":"Yidan Mei, Lutie Chen, Wentao Xu, Chao Liu, Zijian Qiao, Zhihui Lai","doi":"10.1155/2023/9950270","DOIUrl":"https://doi.org/10.1155/2023/9950270","url":null,"abstract":"The benefits of noise can be found in nonlinear systems where a type of resonances can inject the noise into systems to enhance weak signals of interest, including stochastic resonance, vibrational resonance, and chaotic resonance. Such benefits of noise can be improved further by adding some items into the nonlinear systems. Considering the time-dependent memory of fractional-order derivative and time-delay feedback which makes the nonlinear systems take advantage of their historical information and makes the output of nonlinear systems affect the input by feedback control, therefore, we attempt to design the model of stochastic resonance (SR) enhanced by both fractional-order derivative and time-delay feedback. Among them, fractional-order derivative and time delay would reinforce the memory of nonlinear systems for historical information and feedback would use the output of systems to control the systems precisely. Therefore, we hope that their advantages would be fused to improve the weak signal detection performance of SR further. Then, it would be applied to bearing fault diagnosis and compared with that without fractional-order derivative and time-delay feedback and even other diagnostic methods. The experimental results indicate that the SR enhanced by fractional-order derivative and time-delay feedback where a local signal-to-noise ratio is designed as the objective function to optimize these tuning parameters of the proposed method could enhance early fault signature of bearings and outperform that without fractional-order derivative and time-delay feedback and even infogram method.","PeriodicalId":21915,"journal":{"name":"Shock and Vibration","volume":"92 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136294434","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Study on Preload of Bolted Connections in Pitch Bearing Based on Vibration Modal Analysis 基于振动模态分析的节距轴承螺栓连接预紧力研究
4区 工程技术 Q3 ACOUSTICS Pub Date : 2023-10-07 DOI: 10.1155/2023/6653564
Hongwei Zhang, Tao Chen, Kangkang Ji, Meng Zhu, Chengwei Ju
In wind turbine systems, bolted connections are frequently subjected to gravitational and centrifugal loads transmitted by the blades during operation. This can lead to the attenuation of bolt preloading, resulting in bolt loosening or uneven loading, which in turn affects the service life of the generator unit. Therefore, the study of bolt preloading variations is crucial. However, there are numerous factors influencing bolt preloading, and the existing techniques struggle to precisely assess bolt preloading. This paper proposed a bolt preloading evaluation technique based on the hammer modal method. Focusing on the 42CrMo4 bolted connection of a pitch bearing, a test platform for bolt preloading assessment is constructed. Hammer modal tests are conducted under various preloading forces. By combining finite element modal analysis, the correspondence between preloading changes and the bending frequencies and modes of the bolted connection is obtained. The research illustrated that with changes in bolt preloading, variations occur in coherence, phase, and natural frequencies of frequency response functions. The fundamental correlation between bolt preloading and the second-order bending frequency can be utilized to assess changes in preloading. Furthermore, the applicability of this method has been validated, offering a reference for evaluating bolt preloading.
在风力涡轮机系统中,螺栓连接在运行过程中经常受到叶片传递的重力和离心载荷。这可能导致螺栓预紧力衰减,导致螺栓松动或负载不均匀,进而影响发电机组的使用寿命。因此,研究锚杆预紧力的变化是至关重要的。然而,影响锚杆预紧力的因素很多,现有技术难以精确评估锚杆预紧力。提出了一种基于锤模态法的锚杆预紧力评估方法。以某节距轴承42CrMo4螺栓连接为研究对象,搭建了螺栓预紧力评估试验平台。在不同的预紧力下进行了锤模试验。结合有限元模态分析,得到了预紧力变化与螺栓连接弯曲频率和模态的对应关系。研究表明,随着锚杆预压的变化,频率响应函数的相干频率、相位频率和固有频率都会发生变化。锚杆预紧力与二阶弯曲频率之间的基本相关性可以用来评估预紧力的变化。验证了该方法的适用性,为评价锚杆预紧力提供了参考。
{"title":"Study on Preload of Bolted Connections in Pitch Bearing Based on Vibration Modal Analysis","authors":"Hongwei Zhang, Tao Chen, Kangkang Ji, Meng Zhu, Chengwei Ju","doi":"10.1155/2023/6653564","DOIUrl":"https://doi.org/10.1155/2023/6653564","url":null,"abstract":"In wind turbine systems, bolted connections are frequently subjected to gravitational and centrifugal loads transmitted by the blades during operation. This can lead to the attenuation of bolt preloading, resulting in bolt loosening or uneven loading, which in turn affects the service life of the generator unit. Therefore, the study of bolt preloading variations is crucial. However, there are numerous factors influencing bolt preloading, and the existing techniques struggle to precisely assess bolt preloading. This paper proposed a bolt preloading evaluation technique based on the hammer modal method. Focusing on the 42CrMo4 bolted connection of a pitch bearing, a test platform for bolt preloading assessment is constructed. Hammer modal tests are conducted under various preloading forces. By combining finite element modal analysis, the correspondence between preloading changes and the bending frequencies and modes of the bolted connection is obtained. The research illustrated that with changes in bolt preloading, variations occur in coherence, phase, and natural frequencies of frequency response functions. The fundamental correlation between bolt preloading and the second-order bending frequency can be utilized to assess changes in preloading. Furthermore, the applicability of this method has been validated, offering a reference for evaluating bolt preloading.","PeriodicalId":21915,"journal":{"name":"Shock and Vibration","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135252079","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
The Evolution of Vehicle Pneumatic Vibration Isolation: A Systematic Review 汽车气动隔振技术的发展:系统综述
4区 工程技术 Q3 ACOUSTICS Pub Date : 2023-09-29 DOI: 10.1155/2023/1716615
Vincent Akolbire Atindana, Xing Xu, Andrews Nanzie Nyedeb, James Kwasi Quaisie, Jacob Kwaku Nkrumah, Samuel Passim Assam
Whole-body vibration (WBV) is a significant concern for vehicle users as it can negatively impact their health and comfort. As such, effective vibration isolation is critical in vehicle suspension design. The ability of a vehicle suspension to isolate vibrations depends primarily on the suspension design and the type of springs used. One type of spring that has proven advantageous for vibration isolation is the air spring. Air springs can vary frequencies and adjust their stiffness in response to different loading conditions, making them ideal for meeting both suspension load-carrying and occupants’ comfort requirements. Pneumatic (air) suspension has been in use in the automotive industry for several decades and has undergone significant advancements during this period. This paper presents a systematic review of pneumatic suspension since its inception. The review highlights different air spring modeling techniques, types of pneumatic suspension, and control methods. The study also discusses the functional flexibility of pneumatic suspension, its ability to offer a wide range of control options to drivers, and its broad application in almost all ranges of vehicles, including chassis, cabin, and seat suspension systems. In addition, this paper presents a summary of the pros and cons of pneumatic suspension and suggests future research directions. The advantages of pneumatic suspension include effective vibration isolation, improved ride comfort, and the ability to adjust suspension stiffness and ride height. On the other hand, the disadvantages include higher cost and complexity compared to other types of suspension. Overall, the findings of this review demonstrate that pneumatic suspension is a viable solution for vehicle suspension design, particularly in situations where vibration isolation and ride comfort are critical.
全身振动(WBV)是车辆使用者非常关注的问题,因为它会对他们的健康和舒适度产生负面影响。因此,有效的隔振在车辆悬架设计中至关重要。车辆悬架隔离振动的能力主要取决于悬架的设计和所使用的弹簧类型。一种已被证明有利于隔振的弹簧是空气弹簧。空气弹簧可以改变频率,并根据不同的负载条件调整其刚度,使其成为满足悬架承载和乘员舒适性要求的理想选择。气动(空气)悬架已经在汽车工业中使用了几十年,并在此期间取得了重大进展。本文提出了一个系统的回顾,气动悬架自成立以来。这篇综述强调了不同的空气弹簧建模技术、气动悬架类型和控制方法。该研究还讨论了气动悬架的功能灵活性,它能够为驾驶员提供广泛的控制选择,以及它在几乎所有车辆系列中的广泛应用,包括底盘、座舱和座椅悬架系统。此外,本文还对气动悬架的优缺点进行了总结,并提出了今后的研究方向。气动悬架的优点包括有效的隔振,改善乘坐舒适性,以及调节悬架刚度和乘坐高度的能力。另一方面,与其他类型的悬架相比,缺点包括更高的成本和复杂性。总体而言,本综述的研究结果表明,气动悬架是一种可行的车辆悬架设计解决方案,特别是在隔振和乘坐舒适性至关重要的情况下。
{"title":"The Evolution of Vehicle Pneumatic Vibration Isolation: A Systematic Review","authors":"Vincent Akolbire Atindana, Xing Xu, Andrews Nanzie Nyedeb, James Kwasi Quaisie, Jacob Kwaku Nkrumah, Samuel Passim Assam","doi":"10.1155/2023/1716615","DOIUrl":"https://doi.org/10.1155/2023/1716615","url":null,"abstract":"Whole-body vibration (WBV) is a significant concern for vehicle users as it can negatively impact their health and comfort. As such, effective vibration isolation is critical in vehicle suspension design. The ability of a vehicle suspension to isolate vibrations depends primarily on the suspension design and the type of springs used. One type of spring that has proven advantageous for vibration isolation is the air spring. Air springs can vary frequencies and adjust their stiffness in response to different loading conditions, making them ideal for meeting both suspension load-carrying and occupants’ comfort requirements. Pneumatic (air) suspension has been in use in the automotive industry for several decades and has undergone significant advancements during this period. This paper presents a systematic review of pneumatic suspension since its inception. The review highlights different air spring modeling techniques, types of pneumatic suspension, and control methods. The study also discusses the functional flexibility of pneumatic suspension, its ability to offer a wide range of control options to drivers, and its broad application in almost all ranges of vehicles, including chassis, cabin, and seat suspension systems. In addition, this paper presents a summary of the pros and cons of pneumatic suspension and suggests future research directions. The advantages of pneumatic suspension include effective vibration isolation, improved ride comfort, and the ability to adjust suspension stiffness and ride height. On the other hand, the disadvantages include higher cost and complexity compared to other types of suspension. Overall, the findings of this review demonstrate that pneumatic suspension is a viable solution for vehicle suspension design, particularly in situations where vibration isolation and ride comfort are critical.","PeriodicalId":21915,"journal":{"name":"Shock and Vibration","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135193452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Experimental Study on Hydrodynamic Performance of the Integrated Floating Breakwater-Wind Turbine Device 浮式防波堤-风力发电一体化装置水动力性能试验研究
4区 工程技术 Q3 ACOUSTICS Pub Date : 2023-09-29 DOI: 10.1155/2023/6643622
Jianting Guo, Renhao Wu, Xubing Gao, Yuxin Yang
This study presents the design of an integrated floating breakwater-wind turbine device. The hydrodynamic performance was evaluated in a two-dimensional water tank under typical operating conditions to investigate its kinematic response and wave dissipation effect, while the original design was improved and optimized to enhance the overall performance of the integrated device. The improved integrated device had lower heave and sway motion amplitudes, better wave resistance, and better wave dissipation performance than the prototype. The improved integrated device can effectively reduce costs and optimize the allocation of resources by using a floating breakwater as a carrier for wind power generation and has broad application prospects.
本文提出了一种浮式防波堤-风力发电一体化装置的设计。在典型工况下的二维水箱中进行了水动力性能评估,研究了其运动响应和消波效果,同时对原设计进行了改进和优化,提高了集成装置的整体性能。与原型相比,改进后的集成装置具有更小的升沉和摆动运动幅度,更好的抗波能力和更好的消波性能。改进后的集成装置利用浮式防波堤作为风力发电载体,可以有效降低成本,优化资源配置,具有广阔的应用前景。
{"title":"Experimental Study on Hydrodynamic Performance of the Integrated Floating Breakwater-Wind Turbine Device","authors":"Jianting Guo, Renhao Wu, Xubing Gao, Yuxin Yang","doi":"10.1155/2023/6643622","DOIUrl":"https://doi.org/10.1155/2023/6643622","url":null,"abstract":"This study presents the design of an integrated floating breakwater-wind turbine device. The hydrodynamic performance was evaluated in a two-dimensional water tank under typical operating conditions to investigate its kinematic response and wave dissipation effect, while the original design was improved and optimized to enhance the overall performance of the integrated device. The improved integrated device had lower heave and sway motion amplitudes, better wave resistance, and better wave dissipation performance than the prototype. The improved integrated device can effectively reduce costs and optimize the allocation of resources by using a floating breakwater as a carrier for wind power generation and has broad application prospects.","PeriodicalId":21915,"journal":{"name":"Shock and Vibration","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135133426","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Study of Structural and Compression Properties of Soft Soils in Kunming at Different Moisture Contents 昆明地区不同含水率软土结构与压缩特性研究
4区 工程技术 Q3 ACOUSTICS Pub Date : 2023-09-26 DOI: 10.1155/2023/8618546
Wei Guo, Shiguang Xu, Tuo Hong, Shaolei Hao, Gang Chen
The structure of soil refers to the properties and arrangement of soil particles and pores, as well as their interactions, which have a significant impact on the mechanical behavior of soil. Clarifying the strengths and weaknesses of soil structure can effectively ensure engineering safety during designing. In this study, the structural soft soil in the Wujiaba area of Kunming City was studied. A comprehensive structural parameter γ was proposed by analyzing one-dimensional consolidation test data, which consider both the moisture content and yield stress. Due to its high moisture content and lacustrine features, the soft soil in Kunming possessed obvious structural characteristics. As the moisture content increased, the structural characteristics of the soft soil gradually weakened, making it more prone to compression failure. Moreover, the initial consolidation pressure decreased with the increase in moisture content. And the soft soil was more susceptible to deformation failure with higher moisture content. The conclusions drawn from this study have important implications for predicting the settlement of layered soft soil foundations.
土壤结构是指土壤颗粒和孔隙的性质、排列及其相互作用,对土壤的力学行为有重要影响。明确土结构的优缺点,可以有效地保证设计过程中的工程安全。本文以昆明市吴家坝地区的结构性软土为研究对象。通过对一维固结试验数据的分析,提出了考虑含水率和屈服应力的综合结构参数γ。由于高含水率和湖相特征,昆明软土具有明显的结构特征。随着含水率的增加,软土的结构特征逐渐减弱,使其更容易发生压缩破坏。初始固结压力随含水率的增加而减小。软土含水率越高,越容易发生变形破坏。所得结论对层状软土地基沉降预测具有重要意义。
{"title":"Study of Structural and Compression Properties of Soft Soils in Kunming at Different Moisture Contents","authors":"Wei Guo, Shiguang Xu, Tuo Hong, Shaolei Hao, Gang Chen","doi":"10.1155/2023/8618546","DOIUrl":"https://doi.org/10.1155/2023/8618546","url":null,"abstract":"The structure of soil refers to the properties and arrangement of soil particles and pores, as well as their interactions, which have a significant impact on the mechanical behavior of soil. Clarifying the strengths and weaknesses of soil structure can effectively ensure engineering safety during designing. In this study, the structural soft soil in the Wujiaba area of Kunming City was studied. A comprehensive structural parameter <math xmlns=\"http://www.w3.org/1998/Math/MathML\" id=\"M1\"> <mi>γ</mi> </math> was proposed by analyzing one-dimensional consolidation test data, which consider both the moisture content and yield stress. Due to its high moisture content and lacustrine features, the soft soil in Kunming possessed obvious structural characteristics. As the moisture content increased, the structural characteristics of the soft soil gradually weakened, making it more prone to compression failure. Moreover, the initial consolidation pressure decreased with the increase in moisture content. And the soft soil was more susceptible to deformation failure with higher moisture content. The conclusions drawn from this study have important implications for predicting the settlement of layered soft soil foundations.","PeriodicalId":21915,"journal":{"name":"Shock and Vibration","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134887124","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
期刊
Shock and Vibration
全部 Acc. Chem. Res. ACS Applied Bio Materials ACS Appl. Electron. Mater. ACS Appl. Energy Mater. ACS Appl. Mater. Interfaces ACS Appl. Nano Mater. ACS Appl. Polym. Mater. ACS BIOMATER-SCI ENG ACS Catal. ACS Cent. Sci. ACS Chem. Biol. ACS Chemical Health & Safety ACS Chem. Neurosci. ACS Comb. Sci. ACS Earth Space Chem. ACS Energy Lett. ACS Infect. Dis. ACS Macro Lett. ACS Mater. Lett. ACS Med. Chem. Lett. ACS Nano ACS Omega ACS Photonics ACS Sens. ACS Sustainable Chem. Eng. ACS Synth. Biol. Anal. Chem. BIOCHEMISTRY-US Bioconjugate Chem. BIOMACROMOLECULES Chem. Res. Toxicol. Chem. Rev. Chem. Mater. CRYST GROWTH DES ENERG FUEL Environ. Sci. Technol. Environ. Sci. Technol. Lett. Eur. J. Inorg. Chem. IND ENG CHEM RES Inorg. Chem. J. Agric. Food. Chem. J. Chem. Eng. Data J. Chem. Educ. J. Chem. Inf. Model. J. Chem. Theory Comput. J. Med. Chem. J. Nat. Prod. J PROTEOME RES J. Am. Chem. Soc. LANGMUIR MACROMOLECULES Mol. Pharmaceutics Nano Lett. Org. Lett. ORG PROCESS RES DEV ORGANOMETALLICS J. Org. Chem. J. Phys. Chem. J. Phys. Chem. A J. Phys. Chem. B J. Phys. Chem. C J. Phys. Chem. Lett. Analyst Anal. Methods Biomater. Sci. Catal. Sci. Technol. Chem. Commun. Chem. Soc. Rev. CHEM EDUC RES PRACT CRYSTENGCOMM Dalton Trans. Energy Environ. Sci. ENVIRON SCI-NANO ENVIRON SCI-PROC IMP ENVIRON SCI-WAT RES Faraday Discuss. Food Funct. Green Chem. Inorg. Chem. Front. Integr. Biol. J. Anal. At. Spectrom. J. Mater. Chem. A J. Mater. Chem. B J. Mater. Chem. C Lab Chip Mater. Chem. Front. Mater. Horiz. MEDCHEMCOMM Metallomics Mol. Biosyst. Mol. Syst. Des. Eng. Nanoscale Nanoscale Horiz. Nat. Prod. Rep. New J. Chem. Org. Biomol. Chem. Org. Chem. Front. PHOTOCH PHOTOBIO SCI PCCP Polym. Chem.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
0
微信
客服QQ
Book学术公众号 扫码关注我们
反馈
×
意见反馈
请填写您的意见或建议
请填写您的手机或邮箱
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
Book学术官方微信
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术
文献互助 智能选刊 最新文献 互助须知 联系我们:info@booksci.cn
Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。
Copyright © 2023 Book学术 All rights reserved.
ghs 京公网安备 11010802042870号 京ICP备2023020795号-1