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Fatigue and impact analysis and multi-objective optimization design of Mg/Al assembled wheel consideringriveting residual stress

《机械工程前沿(英文)》 2022年 第17卷 第3期 doi: 10.1007/s11465-022-0701-7

摘要: The multi-material assembled light alloy wheel presents an effective lightweight solution for new energy vehicles, but its riveting connection remains a problem. To address this problem, this paper proposed the explicit riveting-implicit springback-implicit fatigue/explicit impact sequence coupling simulation analysis method, analyzed the fatigue and impact performance of the punching riveting connected magnesium/aluminum alloy (Mg/Al) assembled wheel, and constructed some major evaluation indicators. The accuracy of the proposed simulation method was verified by conducting physical experiments of single and cross lap joints. The punching riveting process parameters of the assembled wheel joints were defined as design variables, and the fatigue and impact performance of the assembled wheel was defined as the optimization objective. The connection-performance integration multi-objective optimization design of the assembled wheel considering riveting residual stress was designed via Taguchi experiment, grey relational analysis, analytic hierarchy process, principal component analysis, and entropy weighting methods. The optimization results of the three weighting methods were compared, and the optimal combination of design variables was determined. The fatigue and impact performance of the Mg/Al assembled wheel were effectively improved after optimization.

关键词: magnesium/aluminum assembled wheel     riveting residual stress     fatigue analysis     impact analysis     multi-objective optimization    

Optimal slot dimension for skirt support structure of coke drums

Edward WANG, Zihui XIA

《机械工程前沿(英文)》 2018年 第13卷 第4期   页码 554-562 doi: 10.1007/s11465-018-0513-y

摘要:

The skirt-to-shell junction weld on coke drums is susceptible to fatigue failure due to severe thermal cyclic stresses. One method to decrease junction stress is to add slots near the top of the skirt, thereby reducing the local stiffness close to the weld. The most common skirt slot design is thin relative to its circumferential spacing. A new slot design, which is significantly wider, is proposed. In this study, thermal-mechanical elastoplastic 3-D finite element models of coke drums are created to analyze the effect of different skirt designs on the stress/strain field near the shell-to-skirt junction weld, as well as any other critical stress locations in the overall skirt design. The results confirm that the inclusion of the conventional slot design effectively reduces stress in the junction weld. However, it has also been found that the critical stress location migrates from the shell-to-skirt junction weld to the slot ends. A method is used to estimate the fatigue life near the critical areas of each skirt slot design. It is found that wider skirt slots provide a significant improvement on fatigue life in the weld and slot area.

关键词: coke drum     stress analysis     cyclic stress     fatigue life     skirt slots    

Fatigue evaluation of steel-concrete composite deck in steel truss bridge——A case study

Huating CHEN; Xianwei ZHAN; Xiufu ZHU; Wenxue ZHANG

《结构与土木工程前沿(英文)》 2022年 第16卷 第10期   页码 1336-1350 doi: 10.1007/s11709-022-0852-y

摘要: An innovative composite deck system has recently been proposed for improved structural performance. To study the fatigue behavior of a steel-concrete composite bridge deck, we took a newly-constructed rail-cum-road steel truss bridge as a case study. The transverse stress history of the bridge deck near the main truss under the action of a standard fatigue vehicle was calculated using finite element analysis. Due to the fact that fatigue provision remains unavailable in the governing code of highway concrete bridges in China, a preliminary fatigue evaluation was conducted according to the fib Model Code. The results indicate that flexural failure of the bridge deck in the transverse negative bending moment region is the controlling fatigue failure mode. The fatigue life associated with the fatigue fracture of steel reinforcement is 56 years. However, while the top surface of the bridge deck concrete near the truss cracks after just six years, the bridge deck performs with fatigue cracks during most of its design service life. Although fatigue capacity is acceptable under design situations, overloading or understrength may increase its risk of failure. The method presented in this work can be applied to similar bridges for preliminary fatigue assessment.

关键词: Fatigue assessment     composite bridge deck     rail-cum-road bridge     fatigue stress analysis     Model Code    

液力传动箱上箱体强度分析与优化

刘传峰,田爱琴

《中国工程科学》 2008年 第10卷 第5期   页码 70-74

摘要:

计算机模拟模型分析法是机械设计开发的革命,运用有限元分析法可有效地规避设计风险和失误。对液力传动箱上箱体进行三维建模,提出了力学分析模型,将两个方案进行了有限元分析对比,指导设计方案的改进,提出最终解决方案,解决了设计难题。

关键词: 液力传动箱     力学模型     有限元分析     应力图     静强度     疲劳强度    

A dimensional analysis on asphalt binder fracture and fatigue cracking

Qian ZHAO, Zhoujing YE

《结构与土木工程前沿(英文)》 2018年 第12卷 第2期   页码 201-206 doi: 10.1007/s11709-017-0402-1

摘要: Fracture and fatigue cracking in asphalt binder are two of most serious problems for pavement engineers. In this paper, we present a new comprehensive approach, which consists both of dimensional analysis using Buckingham Theorem and -integral analysis based on classic fracture mechanics, to evaluate the fracture and fatigue on asphalt binder. It is discovered that the dimensional analysis could provide a new perspective to analyze the asphalt fracture and fatigue cracking mechanism.

关键词: Dimensional analysis     asphalt     fracture     fatigue cracking    

随机车辆荷载下三塔悬索桥钢箱梁疲劳关键断面分析

陈策,吉伯海,刘荣

《中国工程科学》 2012年 第14卷 第5期   页码 75-79

摘要:

泰州大桥为世界首座千米级三塔悬索桥,建立泰州大桥的三维全桥模型,通过简化的车辆荷载模型,将随机车流加载于大桥有限元模型上,计算泰州大桥主梁不同位置竖向位移和弯矩的振动响应值,分析车流作用下大桥主梁应力变化最大位置,从而确定主梁的疲劳分析的关键位置。

关键词: 三塔悬索桥     正交异性板     疲劳应力分析     关键截面    

Some remarks on the engineering application of the fatigue crack growth approach under nonzero mean loads

Jorge Alberto Rodriguez DURAN,Ronney Mancebo BOLOY,Rafael Raider LEONI

《机械工程前沿(英文)》 2015年 第10卷 第3期   页码 255-262 doi: 10.1007/s11465-015-0342-1

摘要:

The well-known fatigue crack growth (FCG) curves are two-parameter dependents. The range of the stress intensity factor ?K and the load ratio R are the parameters normally used for describing these curves. For engineering purposes, the mathematical representation of these curves should be integrated between the initial and final crack sizes in order to obtain the safety factors for stresses and life. First of all, it is necessary to reduce the dependence of the FCG curves to only one parameter. ?K is almost always selected and, in these conditions, considered as the crack driving force. Using experimental data from literature, the present paper shows how to perform multiple regression analyses using the traditional Walker approach and the more recent unified approach. The correlations so obtained are graphically analyzed in three dimensions. Numerical examples of crack growth analysis for cracks growing under nominal stresses of constant amplitude in smooth and notched geometries are performed, assuming an identical material component as that of the available experimental data. The resulting curves of crack size versus number of cycles (a vs. N) are then compared. The two models give approximately the same (a vs. N) curves in both geometries. Differences between the behaviors of the (avs. N) curves in smooth and notched geometries are highlighted, and the reasons for these particular behaviors are discussed.

关键词: fatigue crack propagation modeling     life prediction     mean stress effects    

桥面铺装对钢桥面板疲劳应力幅的影响

吴冲,刘海燕,张胜利,崔冰,丁文俊

《中国工程科学》 2010年 第12卷 第7期   页码 39-42

摘要:

钢桥面板厚度小,铺装层的相对刚度较大,钢桥面板疲劳设计时,应该考虑铺装层与钢桥面板的共同作用。假设桥面铺装与顶板没有相对滑移,采用有限元方法探讨了桥面铺装弹性模量和厚度对正交异性钢桥面板疲劳应力幅的影响。

关键词: 桥梁     钢桥面板     桥面铺装     疲劳     应力幅    

Experimental study of surface integrity and fatigue life in the face milling of Inconel 718

Xiangyu WANG, Chuanzhen HUANG, Bin ZOU, Guoliang LIU, Hongtao ZHU, Jun WANG

《机械工程前沿(英文)》 2018年 第13卷 第2期   页码 243-250 doi: 10.1007/s11465-018-0479-9

摘要:

The Inconel 718 alloy is widely used in the aerospace and power industries. The machining-induced surface integrity and fatigue life of this material are important factors for consideration due to high reliability and safety requirements. In this work, the milling of Inconel 718 was conducted at different cutting speeds and feed rates. Surface integrity and fatigue life were measured directly. The effects of cutting speed and feed rate on surface integrity and their further influences on fatigue life were analyzed. Within the chosen parameter range, the cutting speed barely affected the surface roughness, whereas the feed rate increased the surface roughness through the ideal residual height. The surface hardness increased as the cutting speed and feed rate increased. Tensile residual stress was observed on the machined surface, which showed improvement with the increasing feed rate. The cutting speed was not an influencing factor on fatigue life, but the feed rate affected fatigue life through the surface roughness. The high surface roughness resulting from the high feed rate could result in a high stress concentration factor and lead to a low fatigue life.

关键词: roughness     hardness     residual stress     microstructure     fatigue life    

Fatigue stress monitoring and analyses for steel box girder of Runyang Suspension Bridge

WANG Ying, LI Zhaoxia, WU Baijian

《结构与土木工程前沿(英文)》 2008年 第2卷 第3期   页码 197-204 doi: 10.1007/s11709-008-0038-2

摘要: The monitoring of fatigue stress of steel bridge is a key issue of bridge health monitoring and safety assessment. This paper aims to find out the strain history features of the girder components of Runyang Suspension Bridge (RYSB) under vehicle and environmental loading during its first year of service based on the strain-history data recorded by structural health monitoring system installed in the bridge. The fatigue stress spectrums of steel box girders under normal traffic load, heavy trucks and typhoon loads were studied as well as the correlation between varying strain and temperature based on real-time monitoring of temperature histories. The results show that, monitoring on local strain in health monitoring systems of RYSB can effectively provide the information on fatigue stresses. The range of the equivalent fatigue stress on the monitoring location of the bridge is currently low, mainly due to varying traffic loading and temperature. There exists significant correlation between varying temperature and mean value of fatigue stress. Effect of the passing of heavy trucks on bridge fatigue is quite significant since the value of the cumulative fatigue damage generated by heavy trucks is 10 to 100 times larger than that by normal traffic. Therefore, the effect on fatigue cumulative damage due to heavy trucks or overloaded vehicles needs to be monitored and paid much attention to.

关键词: bridge     monitoring location     RYSB     traffic loading     information    

Fatigue crack initiation of magnesium alloys under elastic stress amplitudes: A review

B. J. WANG, D. K. XU, S. D. WANG, E. H. HAN

《机械工程前沿(英文)》 2019年 第14卷 第1期   页码 113-127 doi: 10.1007/s11465-018-0482-1

摘要: The most advantageous property of magnesium (Mg) alloys is their density, which is lower compared with traditional metallic materials. Mg alloys, considered the lightest metallic structural material among others, have great potential for applications as secondary load components in the transportation and aerospace industries. The fatigue evaluation of Mg alloys under elastic stress amplitudes is very important in ensuring their service safety and reliability. Given their hexagonal close packed structure, the fatigue crack initiation of Mg and its alloys is closely related to the deformation mechanisms of twinning and basal slips. However, for Mg alloys with shrinkage porosities and inclusions, fatigue cracks will preferentially initiate at these defects, remarkably reducing the fatigue lifetime. In this paper, some fundamental aspects about the fatigue crack initiation mechanisms of Mg alloys are reviewed, including the 3 followings: 1) Fatigue crack initiation of as-cast Mg alloys, 2) influence of microstructure on fatigue crack initiation of wrought Mg alloys, and 3) the effect of heat treatment on fatigue initiation mechanisms. Moreover, some unresolved issues and future target on the fatigue crack initiation mechanism of Mg alloys are also described.

关键词: Mg alloys     fatigue behavior     microstructure     crack initiation     deformation mechanism    

Hierarchical approach for fatigue cracking performance evaluation in asphalt pavements

Ibrahim ONIFADE, Yared DINEGDAE, Björn BIRGISSON

《结构与土木工程前沿(英文)》 2017年 第11卷 第3期   页码 257-269 doi: 10.1007/s11709-017-0410-1

摘要: In this paper, a hierarchical approach is proposed for the evaluation of fatigue cracking in asphalt concrete pavements considering three different levels of complexities in the representation of the material behaviour, design parameters characterization and the determination of the pavement response as well as damage computation. Based on the developed hierarchical approach, three damage computation levels are identified and proposed. The levels of fatigue damage analysis provides pavement engineers a variety of tools that can be used for pavement analysis depending on the availability of data, required level of prediction accuracy and computational power at their disposal. The hierarchical approach also provides a systematic approach for the understanding of the fundamental mechanisms of pavement deterioration, the elimination of the empiricism associated with pavement design today and the transition towards the use of sound principles of mechanics in pavement analysis and design.

关键词: fatigue cracking     energy based     crack initiation     mechanistic approach     pavement analysis    

Assessment of fatigue life of remanufactured impeller based on FEA

Lei XU,Huajun CAO,Hailong LIU,Yubo ZHANG

《机械工程前沿(英文)》 2016年 第11卷 第3期   页码 219-226 doi: 10.1007/s11465-016-0394-x

摘要:

Predicting the fatigue life of remanufactured centrifugal compressor impellers is a critical problem. In this paper, the S-N curve data were obtained by combining experimentation and theory deduction. The load spectrum was compiled by the rain-flow counting method based on the comprehensive consideration of the centrifugal force, residual stress, and aerodynamic loads in the repair region. A fatigue life simulation model was built, and fatigue life was analyzed based on the fatigue cumulative damage rule. Although incapable of providing a high-precision prediction, the simulation results were useful for the analysis of fatigue life impact factors and fatigue fracture areas. Results showed that the load amplitude greatly affected fatigue life, the impeller was protected from running at over-speed, and the predicted fatigue life was satisfied within the next service cycle safely at the rated speed.

关键词: remanufactured impeller     fatigue life     impeller failures     finite element analysis (FEA)    

变幅载荷下纤维金属层板的疲劳与寿命预测

吴学仁,郭亚军

《中国工程科学》 1999年 第1卷 第3期   页码 35-40

摘要:

文章建立了纤维金属层板等幅疲劳载荷下的疲劳裂纹扩展速率与寿命预测模型。在此基础上对玻璃纤维-铝合金层板(GLARE)的疲劳裂纹扩展与分层扩展行为进行了试验研究,探讨了层板过载疲劳行为的机理,提出了纤维金属层板变幅载荷下疲劳寿命预测的等效裂纹闭合模型,并在GLARE层板上得到了验证。

关键词: 纤维金属层板     疲劳     桥接     分层     寿命预测    

Evaluation method of multiaxial low cycle fatigue life for cubic single crystal material

CHEN Jiping, DING Zhiping

《机械工程前沿(英文)》 2007年 第2卷 第3期   页码 278-282 doi: 10.1007/s11465-007-0048-0

摘要: The coupling effect of normal stress and shear stress on orthotropic materials happens when applied loading deflects from the directions of the principal axes of the material coordinate system. By taking account of the coupling effects, formulas of equivalent stress and strain for cubic single crystal materials are cited. Using the equivalent strain and equivalent stress for such material and a variable k, which is introduced to express the effect of asymmetrical cyclic loading on fatigue life, a low cycle fatigue (LCF) life prediction model for such material in multiaxial stress starts is proposed. On the basis of the yield criterion and constitutive model of cubic single crystal materials, a subroutine to calculate the thermo elastic-plastic stress-strain of the material on an ANSYS platform was developed. The cyclic stress-strain of DD3 notched specimens under asymmetrical loading at 680vH was analyzed. Low cycle fatigue test data of the single crystal nickel-based superalloy are used to fit the different parameters of the power law with multiple linear regression analysis. The equivalent stress and strain for a cubic single crystal material as failure parameters have the largest correlation coefficient. A power law exists between k and the failure cycle. The model was validated with LCF test data of CMSX-2 and DD3 single crystal nickel-based superalloys. All the test data fall into the factor of 2.5 for CMSX-2 hollow cylinder specimens and 2.0 scatter band for DD3 notched specimens, respectively.

关键词: orthotropic     regression analysis     crystal material     multiaxial     prediction    

标题 作者 时间 类型 操作

Fatigue and impact analysis and multi-objective optimization design of Mg/Al assembled wheel consideringriveting residual stress

期刊论文

Optimal slot dimension for skirt support structure of coke drums

Edward WANG, Zihui XIA

期刊论文

Fatigue evaluation of steel-concrete composite deck in steel truss bridge——A case study

Huating CHEN; Xianwei ZHAN; Xiufu ZHU; Wenxue ZHANG

期刊论文

液力传动箱上箱体强度分析与优化

刘传峰,田爱琴

期刊论文

A dimensional analysis on asphalt binder fracture and fatigue cracking

Qian ZHAO, Zhoujing YE

期刊论文

随机车辆荷载下三塔悬索桥钢箱梁疲劳关键断面分析

陈策,吉伯海,刘荣

期刊论文

Some remarks on the engineering application of the fatigue crack growth approach under nonzero mean loads

Jorge Alberto Rodriguez DURAN,Ronney Mancebo BOLOY,Rafael Raider LEONI

期刊论文

桥面铺装对钢桥面板疲劳应力幅的影响

吴冲,刘海燕,张胜利,崔冰,丁文俊

期刊论文

Experimental study of surface integrity and fatigue life in the face milling of Inconel 718

Xiangyu WANG, Chuanzhen HUANG, Bin ZOU, Guoliang LIU, Hongtao ZHU, Jun WANG

期刊论文

Fatigue stress monitoring and analyses for steel box girder of Runyang Suspension Bridge

WANG Ying, LI Zhaoxia, WU Baijian

期刊论文

Fatigue crack initiation of magnesium alloys under elastic stress amplitudes: A review

B. J. WANG, D. K. XU, S. D. WANG, E. H. HAN

期刊论文

Hierarchical approach for fatigue cracking performance evaluation in asphalt pavements

Ibrahim ONIFADE, Yared DINEGDAE, Björn BIRGISSON

期刊论文

Assessment of fatigue life of remanufactured impeller based on FEA

Lei XU,Huajun CAO,Hailong LIU,Yubo ZHANG

期刊论文

变幅载荷下纤维金属层板的疲劳与寿命预测

吴学仁,郭亚军

期刊论文

Evaluation method of multiaxial low cycle fatigue life for cubic single crystal material

CHEN Jiping, DING Zhiping

期刊论文