摘要
疲劳试验数据一般属小子样范畴,在Weibull寿命分布的假设下应考虑特征寿命的统计置信度。总结特征寿命概率估计的贝叶斯法和虚拟增广样本的Bootstrap法,通过2024-T3直耳片的七组疲劳试验数据对二者进行对比和评估。针对EDF拟合检验法无法对特征寿命估计值的合理性提供实质性指导的问题,提出一种新的试验样本数据全部落入寿命分布(1-a)双侧百分位区间的判定方法。结果表明:Bootstrap法的特征寿命估计值比贝叶斯法偏大;本文提出的判定方法可有效定性判断特征寿命估计值偏大或偏小。
The number of fatigue test data is generally small, thus under the assumption of Weibull distribution, the statistical confidence of characteristic life should be taken into consideration. Probability estimation methods of characteristic life are summarized, such as Bayesian method and Bootstrap method of virtually expanded sam- ple. Then seven groups of fatigue test data for straight lugs are applied for comparison of these methods. Be cause EDF fitting methods can＇t offer substantial guidance to the rationality of characteristic life＇s estimations, a new method is proposed that all the test data should fall into （1-a） percentile interval of the life distribution. Through comparison and analysis, it can be concluded that estimations by Bayesian method are smaller than that of Bootstrap method, and the proposed statistical method is effective qualitatively to judge how about the estimation of characteristic life.
出处
《航空工程进展》
2013年第4期515-521,共7页
Advances in Aeronautical Science and Engineering
