中文摘要：

疲劳寿命预报需要知道在全设计寿命期内的疲劳载荷时间历程或载荷谱的信息。但是,在很多情况下,实际测量或模拟的载荷时间历程与设计寿命相比只包含很短的一段时间。如何将测量的数据外插到更长的时间段以及如何计数出每周的信息是疲劳分析中必须要解决的两个重要问题。文中的主要目的就是介绍一种将实测载荷外插的方法以及雨流计数法。这两种方法均被编成相应的计算程序。一条水面船的实测数据用作例子来演示计算过程。最后对如何采用这两种方法来构建疲劳设计载荷问题也提出了思路。

英文摘要：

Fatigue life prediction requires the information of fatigue loading history or spectrum over the whole design life.However,in many cases,the measured or simulated load history only includes a very short time compared to the entire design life.How to extrapolate the measured loads to longer time and how to count the information for every cycle are two important problems to be solved in fatigue analysis.In this paper,a method to extrapolate the measured loads to longer time is introduced together with the rainflow cycle counting method.Both methods have been implemented into computer programs.An example calculation is given to show the process.Problems on how to use these two methods to determine the design load are also pointed out.