疲劳的

The fatigue life followed the logarithmic normal distribution or the two-parameter Weibull distribution by the probability regression method.

为研究预腐蚀对疲劳寿命的影响，进行30CrMnS iN i2A和LC4CS试件加速预腐蚀不同时间后的成组随机谱下的疲劳试验，采用概率回归方法对预腐蚀疲劳寿命分布特性进行检验，表明可采用对数正态分布和双参数威布尔分布描述疲劳寿命分布特性。

The effect of undissolved ferrite amount on contact, impact and bending fatigue properties were studied. The stress relaxation and grain refinement due to occurring of plastic deformation are main reasons of improving the fatigue life.

就未溶铁素体含量对接触疲劳、多冲疲劳及弯曲疲劳性能的影响机理进行研究，局部的应力集中因铁素体发生塑变而得到松弛和细化晶粒是提高疲劳寿命的主要原因。

The antifatigue function of more than forty kinds of insect,fungi,bacteria and algae was studied and sifted first in this study by detecting swimming endurance and biochemical indexes. Then,in order to choose the better ones from the compoud additives formulas composed of L-carnitine, taurine, octacosanol,vitaminE and insectA ,a cross design experiment was done. InsectA was discovered in the first experiment that it greatly improved the antifatigue function in mice. Finally, the acute toxicities, thirty-day feeding effects and the mechanisms of No. 1 antifatigue compoud additives(No.1ACF) were studied.

本研究首先通过小鼠游泳耐力试验和血液生化指标的测定对40余种昆虫、菌藻的抗疲劳作用进行了筛选；在此基础上，应用正交设计方法对以L-肉碱、二十八醇、牛磺酸和本实验筛选出的抗疲劳功效较好的昆虫A为原料的配方进行了抗疲劳作用筛选，并对筛选出的最佳配方，即抗疲劳复方添加剂1号配方进行了小鼠急性经口毒性试验、30天喂养试验和抗疲劳作用机理研究。

The results show that wet air reduces both fatigue life and strength with the influence-factor of 0.6059 and 0.8722, respectively. Wet air environment enlarges the dispersivity of fatigue life, therefore using the corrosion-influence-factor obtained by eigenvalue or mean value to predict the fatigue life with high reliability will cause an unconservative conclusion.

结果表明，潮湿空气环境显著降低了2024-T3铝合金的疲劳性能，潮湿空气环境对其疲劳寿命特征值和疲劳强度均值的影响系数分别为0.6059和0.8722；在潮湿空气环境中疲劳寿命的分散性变大，用疲劳寿命的中值或特征值得到的腐蚀影响系数进行可靠度95%的腐蚀环境下的寿命修正，将得到偏危险的结果。

So it is necessary to study fatigue damage and predict the fatigue life of guyed mast in order to provide important basis for guyed mast on evaluation of fatigue residual life and proposition of new method of fatigue damage detection.

因此有必要进行桅杆结构的疲劳损伤分析及疲劳寿命预测，为桅杆结构疲劳剩余寿命评估以及疲劳损伤监测新方法的提出提供重要依据。

By measuring the residual stresses of the cylinder of a cement ball mill in four cases,and the fatique crack spreading for the thermal treatment and the un thermal treatment test samples,the results showed that the heat treatment sample reduced the residual stress,enhanced the fatique strength and lowered the crack spreading speed.

对球磨机筒体的4种情况的焊件进行残余应力测试，并对进行热处理和未进行热处理的试件做疲劳试验及疲劳裂纹扩展测试。试验结果表明：经过热处理的试件，残余应力降低，疲劳强度提高，裂纹扩展速率降低，结构抗疲劳性能增强。不过从工程应用角度看，对于板厚为20～25mm的球磨机筒体而言，不进行焊后热处理也能保证足够的疲劳强度

The results of low-cycle fatigue tests were used to analyze fatigue life curve of pressure vessel.

把低周疲劳特征研究结果应用于压力容器疲劳寿命曲线分析，并将焊缝实验结果与著名的Langer疲劳计算曲线及美国ASME规范设计曲线进行了比较，为16MnR钢焊接压力容器的疲劳寿命设计提供了理论依据。

To solve the problem, a three-point bending test was put forward.

中文摘要：针对以Q450NQR1钢为基板、B级钢为腹板模拟实际工装位置，疲劳断裂与货车运营实际工况不符的问题，提出以B级钢为基板、Q450NQR1钢为腹板进行三点弯曲疲劳试验，诱使疲劳裂纹向B级钢侧扩展，研究了MAG气体保护焊B级钢/Q450NQR1钢搭接接头的疲劳性能。

With analysing the the fatigue mechanism, the general mode of interply fatigue damage propagation is denoted by delamination length and crack density. Based on the power-law, the relationship between number of cycles and delamination length and crack density are established. The specimen is modeled as an equivalent six-ply material system. Starting with the analysis of interply stress, the interply shear stress under cyclic loading is calculated by using nonlinear three-demension FEA. According to the stage regularity of fatigue damage propagation, such models as average strain, effective modulus, ratio of delamination length and crack density, experimental relationship between crack density and effective modulus, are proposed by introducing subsection coefficient.

通过对疲劳机理的分析，确定了以脱层长度和裂纹密度表示的层间疲劳损伤演化的一般模式，利用指数法则建立了脱层长度和裂纹密度随疲劳循环周次变化的关系；从层间应力分析入手，以等效六层的材料模型对循环载荷下的层间剪切应力进行了三维非线性有限元分析；根据疲劳损伤扩展的阶段性，引入分段系数，分别建立了平均应变与载荷循环周次的分段线性模拟模型、有效刚度随载荷循环周次的变化关系模型、裂纹密度变化和脱层长度变化关系随载荷循环周次变化的分段线性模型以及疲劳裂纹密度和有效刚度关系的经验模型。

Two types of single-ply materials, polyester cord reinforced rubber composite and rayon cord reinforced rubber composite, are firstly studied. The essential fatigue properties and rules under cyclic loading are obtained The fatigue mechanism was analysed in terms of fatigue life curve. This part of work lays foundation for catching the experiment information, analyzing the experimental results, confirming the influence factors and explaining the experimental phenomena.

作为试验基础，首先对聚酯帘线和人造丝帘线增强的橡胶复合材料单层板的疲劳进行研究，获得了橡胶复合材料在循环载荷下基本的疲劳特性和规律，并结合疲劳寿命图对疲劳损伤机理进行了分析，在试验信息获取、试验结果分析、影响因素确定、试验现象解释等方面为橡胶复合材料的疲劳研究奠定了基础。

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