航空学报 > 1992, Vol. 13 Issue (3): 232-235

伪随机谱载荷下的可靠性模型

费斌军   

  1. 北京航空航天大学飞行器设计和应用力学系 北京 100083
  • 收稿日期:1991-07-13 修回日期:1991-09-10 出版日期:1992-03-25 发布日期:1992-03-25

A RELIABILITY MODEL OF THE STRUCTURE UNDER RANDOM LOADS

Fei Bin-jun   

  1. Department of Flight Vehicle Design and Applied Mechanic, Beijing University of Aeronautics and Astronautics,Beijing, 100083
  • Received:1991-07-13 Revised:1991-09-10 Online:1992-03-25 Published:1992-03-25

摘要:

齐次马尔可夫模型可以用于描述伪随机谱载荷下的裂纹扩展的随机过程。文中导出了用初始裂纹长度的分布及马尔可夫转移概率密度函数计算给定时刻裂纹长度分布的积分公式。建立了由实验数据估计马尔可夫转移概率密度函数的计算方法。在此基础上建立了计及裂纹检出概率的可检结构的可靠性模型。

关键词: 结构可靠性, 裂纹扩展, 马尔可夫过程

Abstract:

The fatigue crack growth under the random loads is described by a time discrete Markoff process. The distribution function of crack length at given time can be calculated by integration of the initial crack length distribution and the transition function of Markoff process. The transition function can be identified with experience crack growth data. The structure reliability is calculated by intersection of the probability density function of crack length and distribution function of critic crack length. A time-dependent reliability model accounting the crack inspected probability for inspectable structure is established.

Key words: reliability of structure, fatigue crack growth, Markoff process