航空学报 > 2000, Vol. 21 Issue (2): 118-123

飞机高置信度中值随机疲劳载荷谱的编制原理

阎楚良, 高镇同   

  1. 北京航空航天大学固体力学研究所 北京 100083
  • 收稿日期:1999-11-16 修回日期:1999-12-27 出版日期:2000-04-25 发布日期:2000-04-25

COMPILATION THEORY OF MEDIAN STOCHASTIC FATIGUE LOAD SPECTRUM WITH HIGH CONFIDENCE LEVEL FOR AIRPLANE

YAN Chu-liang, GAO Zhen-tong   

  1. Institute of Solid Mechanics, Beijing University of Aeronautics and Astronautics, Beijing 100083, China
  • Received:1999-11-16 Revised:1999-12-27 Online:2000-04-25 Published:2000-04-25

摘要:

借助于当量寿命概率分布,在满足高置信度 ( 90 %以上 )条件下,提出了中值随机疲劳载荷谱的编制原理。中值随机疲劳载荷谱与确定飞机使用寿命的分散系数法相关一致,能够真实地展现结构在实际工作中的自然形态载荷—时间历程,保持了载荷—时间和各个状态参数的一一对应关系。进行疲劳试验时,能够真实地再现结构关键部位疲劳损伤依赖于时间的裂纹萌生、裂纹扩展和断裂的全过程。

关键词: 高置信度, 中值, 载荷谱, 编制原理

Abstract:

In view of the compilation of airplane load spectrum having close relation with the national conditions and the compilation method subordinate to knowledge property category, in the research, we find another way, rely on our own efforts and have set up a technical approach to airplane load spectrum compilation with China characteristics. With the help of equivalent life probability distribution and under the condition of satisfying a high confidence level (above 90%), we put forward a compilation theory of median stochastic fatigue load spectrum. Median stochastic fatigue load spectrum agrees to the scatter factor method of determining airplane service life. It can truly display the load time history of structural natural modality in the real service. It keeps a one to one correspondence relation of load time and every state parameter. When fatigue testing is done, median load spectrum can authentically replay the whole fatigue damage procedure of structural key parts depending on the time of crack generation, crack propagation and final fracture.

Key words: high confidence level, median, load-spectrum, compilation theory