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高弹模CFRP粘贴法修复钢桥板疲劳裂纹

open access: yesJianzhu Gangjiegou Jinzhan, 2022
针对钢桥中钢板疲劳裂纹进行了一系列疲劳裂纹修复试验研究,以确定不同修复方法下结构的疲劳性能。高弹模CFRP(碳纤维增强复合材料)修复法是通过粘贴高弹模CFRP布来增大结构刚度,以延长结构疲劳寿命,且碳纤维材料基本不会产生疲劳裂纹,具有较好的抗疲劳效果。采用数值模拟和试验研究相结合的方法,首先对修复钢板的应力分布和特点进行了详细的分析,然后通过3组对比疲劳试验,确定了不同修复方法对损伤钢板疲劳寿命的增强效果。最后利用修复试验值与各国规范规定的S-N曲线进行比较,分析已修复钢板的疲劳性能。研究结果表明 ...
吕志林   +4 more
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波纹腹板H形钢吊车梁疲劳寿命有限元分析

open access: yesJianzhu Gangjiegou Jinzhan, 2021
利用Matlab程序模拟吊车梁变幅应力荷载谱并采用考虑低应力幅值影响的疲劳曲线,应用有限元分析方法,将波纹腹板H形钢吊车梁与具有相同承载力极限和荷载边界条件的普通平截面H形钢吊车梁的疲劳寿命进行比较。结果表明,波纹腹板H形钢吊车梁相对于普通平截面H形钢吊车梁的整体疲劳性能和疲劳寿命均得到了较大的提升。此外,通过改变腹板构件的波纹尺寸对结构的疲劳寿命进行了参数分析,包括波纹腹板的波纹高度、波纹长度和波纹倾角,系统地研究了波形腹板H形钢吊车梁的疲劳寿命,最后结合波纹腹板在不同尺寸时的钢材使用量 ...
徐忠根, 郭轩, 邓长根
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基于NSGA-Ⅱ的开口肋钢-UHPC组合桥面多目标优化

open access: yesJianzhu Gangjiegou Jinzhan, 2023
为研究开口肋正交异性钢-超高性能混凝土(UHPC)组合桥面的疲劳性能,通过子模型法建立实体-壳单元有限元模型,获得了轮载作用下疲劳敏感细节的应力响应。分析得出,所有疲劳细节应力水平均不大,除了纵肋-横隔板接头处横隔板细节属于有限寿命外,其余疲劳细节均可实现无限寿命。结合试验设计与响应面法,得到了横隔板侧细节应力幅的构造参数回归模型,可不开展数值分析,立即提取给定构造参数下的横隔板侧细节应力幅。为进一步实现横隔板侧细节的无限疲劳寿命设计,采用NSGA-Ⅱ算法对结构开展多目标优化。通过Pareto前沿面得出:
向泽, 祝志文
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Ultrasonic Vibration Assisted Laser Processing: A Hybrid Paradigm for Extreme Surface Enhancement

open access: yesRare Metals, Volume 45, Issue 10, October 2026.
ABSTRACT Traditional laser processing techniques offer many advantages, but they often encounter limitations such as heat‐affected zones, recast layers, residual tensile stresses, and poor surface finish. The integration of ultrasonic vibration (UV) presents a promising hybrid approach to overcome these challenges by introducing beneficial effects like
Aziz Ul Hassan Mohsan   +6 more
wiley   +1 more source

Multilayer Architecture of PVD/HVOF Coatings Enables Transition in Wear Mechanism and Enhanced Tribological Performance

open access: yesRare Metals, Volume 45, Issue 9, September 2026.
ABSTRACT TiN films deposited by physical vapor deposition (PVD) are widely used as protective films due to their high hardness and wear resistance. However, their application under high‐load conditions is limited by poor load‐bearing capacity and susceptibility to spalling on soft substrates.
Ziyu Wang   +6 more
wiley   +1 more source

In Situ Investigation on the Roles of Microstructural Characteristics in Fatigue Anisotropy and Crack Propagation of LPBF–IN718 Alloy

open access: yesRare Metals, Volume 45, Issue 7, July 2026.
ABSTRACT Laser powder bed fusion (LPBF) of Inconel 718 alloy inevitably introduces pronounced microstructural anisotropy, typified by columnar grains and robust crystallographic texture. This results in direction‐dependent fatigue behavior, raising critical reliability concerns for high‐stakes aerospace applications.
Zhifang Shi   +9 more
wiley   +1 more source

High‐Cycle Fatigue Behavior and Deformation Mechanisms of Al0.5CoCrFeNi High‐Entropy Alloy by Laser Powder Bed Fusion

open access: yesRare Metals, Volume 45, Issue 5, May 2026.
ABSTRACT Laser powder bed fusion (LPBF) can fabricate high‐entropy alloys (HEAs) with refined microstructure and enhanced mechanical properties. However, the deformation and fatigue mechanisms of Al‐containing HEAs produced by LPBF remain unclear. In this work, we systematically investigate the tensile properties, deformation mechanisms, and high‐cycle
Dan Zheng   +4 more
wiley   +1 more source

复杂应力状态下桩腿节点多轴疲劳寿命评估

open access: yesHaiyang gongcheng zhuangbei yu jishu, 2015
引入了一种多轴疲劳寿命评估方法,并对该方法的疲劳评估流程进行研究.使用该方法联合热点应力法对国际公开发表的250多个疲劳试验数据进行多轴疲劳寿命预测,验证了该方法多轴疲劳寿命预测的精确度.最后使用该方法成功对自升式平台K型桩腿节点进行了多轴疲劳寿命评估,可为提高桩腿节点疲劳寿命预测的准确性提供有益参考.
刘英芳   +5 more
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基于ANSYS分析软件的海洋平台局部构造疲劳寿命评估研究

open access: yesHaiyang gongcheng zhuangbei yu jishu, 2015
疲劳损伤失效是海洋结构面临的重要问题,而对于裙桩套筒这样的局部复杂结构而言,疲劳寿命评估更为关键。应用ANSYS软件建立了一套海洋平台局部构造疲劳寿命评估流程,通过热点应力外推法,采用疲劳的简化分析方法计算疲劳寿命,并运用该方法验证了某平台裙桩套筒满足疲劳要求。该方法利用了局部结构强度分析的ANSYS应力分析结果,得到的应力幅值更加合理、便利,同时将热点应力外推法融入到疲劳简化分析方法中,具有较高的工程应用价值,可为今后海洋平台其他典型局部构造的疲劳寿命评估提供指导。
冯加果   +3 more
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超声冲击处理焊接节点疲劳性能改善及寿命预测方法研究进展

open access: yesJianzhu Gangjiegou Jinzhan, 2023
对超声冲击处理焊接节点疲劳寿命提高及其机理和疲劳寿命预测方法的研究现状及研究不足进行了综述。目前研究表明超声冲击处理通过改变焊趾局部几何形状从而降低该部位的应力集中、在焊趾部位引入残余压应力和消除焊趾部位焊接缺陷并细化局部晶粒可以有效地提高焊接节点的疲劳寿命,然而目前的研究对象主要针对焊接后立即进行超声冲击处理的焊接节点,针对实际工程中已经服役一定时间的焊接节点开展的相关研究较少。此外,实际工程中的焊接节点在进行超声冲击处理时一般处于持荷状态 ...
李涛, 汪洋, 甘进, 邵永波
doaj  

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