疲劳的

The fatigue reliability analysis for the 16V240ZJB diesel engine crankshaft inserving DF4B internal-combustion locomotive were carried out in thisdissertation.Firstly,according to the fatigue loads of the crankshaft,the bendstress and torsion stress at danger zone in rated operation modes werecalculated respectively.The stress randomicity of the crankshaft was analyzedrelating operation modes of acceptance,and the probability distribution ofstresses were obtained with statistical analysis.

运用本文所提出的疲劳可靠性分析模型(干涉模型-Miner准则综合法及弯扭复合模型)和经分析简化得到的材料p-S-N曲线和p-Sa-Sm-N曲面，分别按一维、二维疲劳应力及弯扭复合应力三种情况对东风4B型内燃机车16V240ZJB柴油机曲轴进行了疲劳可靠性分析。

Aimed at the crankshaft fatigue of certain typed 4 cylindered internal combustion engine this paper established the dynamics model of piston-shaft system and carried out simulation.A...

文中针对某型号4缸内燃机曲轴疲劳，建立了活塞-轴系动力学模型并进行仿真，然后把仿真结果转化为时间载荷传递到曲轴的有限元计算模型中，最后对该有限元模型进行疲劳仿真，从而获得整个曲轴的疲劳寿命计算结果。

Experiments are conducted to determine the gigacycle fatigue behavior of nodular cast iron GS51 by ultrasonic fatigue test system.

应用超声疲劳试验技术，完成了20kHz频率下(R=-1，R=0 1)的疲劳试验，获得球墨铸铁GS51在亿周次范围内的疲劳性能。

The successfully designed steel ropes with the specialized ground tackle,which is used to connect with experimental machine,together with a set of revised casting technology of steel rope ends that used in labs can be used in relevant researches.In the research the following significant achievements are made:a set of S-N diagrams and their equations,Goodman Smith figures and an empirical f...

设计成功的钢丝绳与试验机联接的专用锚具、优化出的一套试验室条件下的绳头浇铸工艺，可应用于相关研究工作；研究得到的S -N曲线族及其曲线方程、Goodman -Smith图和疲劳强度计算经验公式、钢丝绳的拉伸疲劳性能和疲劳破坏规律、从宏、微观两个方面对钢丝绳疲劳破坏机理进行的初步研究等等，对钢丝绳结构工程设计人员具有一定的参考价值。

To the question of fatigue invalidating of strain gages in dynamic test(normally the zero drift value being bigger than the permissible value),the equations for calculating the fatigue life of the strain gages are derived on the basis of the fracture mechanics theory.

针对应变片在长时间的动态测试中疲劳失效(一般是测量误差超过允许值)问题，本文从疲劳断裂力学的基本理论出发，导出了应变片疲劳寿命的计算公式；实验表明，实验曲线与理论曲线吻合，这证明我们推导的公式的正确性，为应变片的疲劳寿命的预测、许可载荷的确定、失效判据的确立提供了理论基础。

The present work focuses on delamintion failure of two-ply steel cord-rubber composite . The growth of fatigue damage, the modes of fatigue failure, the effect factors on fatigue life, the hysteretic loss and the variation of temperature are studied in detail.

因此，本文采用双层钢丝帘线／橡胶复合材料，重点研究了材料在循环载荷作用下的脱层破坏，对疲劳损伤的扩展、疲劳破坏模式、疲劳寿命影响因素、滞后损失和温升特性进行了详细分析。

So the braking prescription should be performed strictly, furthermore, the sudden and urgent braking should be avoided to the best of our abilities.In the end, the thermal fatigue lives were evaluated by the finite element method. It was proved that the thermal fatigue life of improved steel (ZG35CrMoRE) was higher than that of the formers. It was also found that the quantitative evaluations of the thermal fatigue lives of brake disc were acquirable, by putting the equivalent plastic strain, which was analyzed with finite element methods, and the material mechanical property parameters into the formula of Manson-Coffon to calculate its lives. Therefore, theoretical method can be provided to develop new brake disc steel and to prolong its lives.

为了进一步提高刹车鼓的使用寿命，对新试制的钢种进行了热疲劳寿命评估，验证了改进后的钢种在相同的使用工况下具有更高的热疲劳寿命；评估结果还表明利用有限元数值分析计算相应的等效塑性应变，结合材料力学性能参数，代入Manson-Coffin热疲劳寿命公式可以对刹车鼓的热疲劳寿命做出定量评估，从而为刹车鼓用钢的研制和刹车鼓寿命的提高提供了理论依据。

This paper discusses failure pattern and force of link chain hook of link chain bucket elevator, finds out the causes of short periodical fatigue failure of link chain hook and points out the key factors that influence fatigue life of the link chain hook is the fitting gap .

通过对环链斗式提升机链环钩失效形式和受力情况的分析，揭示了链环钩产生低周疲劳失效的原因，指出了在影响链环钩疲劳寿命的诸多因素中，链环钩与料斗之间的装配间隙是决定其疲劳寿命的主要因素，重新设计的链环钩解决了疲劳断裂问题，说明设计中所采取的措施是有效的。

First, the theory of fretting wear and studies on fretting fatigue were introduced and the parametric method was used in the process of creating the model of dovetail joints in UG software. The elastic contact problem is analyzed in finite element method and is used to the parameters' distribution and contact stress of the joint are obtained on the base of ANSYS code. With the effect factor of load frequency, the prediction method of fretting fatigue life of dovetail joint under low and high/low cycle complex load is proposed. The proposed model and the approach were verified by experiments.

本文介绍了微动损伤的机理和微动疲劳寿命的研究方法；利用UG软件对燕尾榫联接结构创建了参数化实体模型；基于ANSYS软件平台求解弹性接触问题，获得了榫联接结构接触应力及接触状态量的分布；在已有微动疲劳寿命预测模型的基础上，引入载荷频率影响因子，对低周、高低周复合载荷作用下的燕尾榫联接结构进行了微动疲劳寿命的预测，与试验结果对比表明采用本文提出的方法预测榫联接结构的微动疲劳寿命是有效的。

These are references of theory and test for safety assess of reactors. The paper put forward the concept of decrease coefficient , and the actual calculation process of K〓 for forecasting the fatigue life of the structure. The research made it possible to forecast the fatigue life of damaged materials, and the prediction was based on the S-N curve from the fatigue test of the smooth material with controlled strain.

提出了疲劳寿命的减少系数K〓的概念，给出了计算K〓预测结构的疲劳寿命的具体过程，这一问题的研究使以平滑材料控制应变疲劳试验得出的S-N曲线图为基础来预测有损伤材料的疲劳寿命成为可能。

In the negative and interrogative forms, of course, this is identical to the non-emphatic forms.

。但是，在否定句或疑问句里，这种带有"do"的方法表达的效果却没有什么强调的意思。

Go down on one's knees;kneel down

屈膝跪下。。。下跪祈祷