飞机典型结构(紧固孔)原始疲劳质量研究

A STUDY ON INITIAL FATIGUE QUALITY OF TYPICAL AIRCRAFT STRUCTURES (FASTENER HOLES)

本文介绍了一个定量地确定飞机结构细节(紧固孔)的原始疲劳质量的工程方法。用“当量初始缺陷尺寸分布”表征在一个或多个结构细节中真实初始缺陷的当量影响。用“使用裂纹扩展控制曲线”描述这一分布的扩展规律。用“裂纹超出量概率”定量地确定细节疲劳开裂的损伤度。这一工程方法原则上也适用于其它的结构细节,如几何不连续处、圆角及耳片等。本文编制了参数优化的计算机程序,并进行了大量试验研究,计算结果证实了这一工程方法的适用性、

In this paper, an engineering approach for determining initial fatigue quality(IFQ) of aeronautic structure details (fastener holes) is introduced. The equivalent effects of a physic -al initial flaw on one or multiple structure details are characterized by equivalent initial flaw size (E1FS) distribution.The growth law of this distribution is described by servie crack growth master curve (SCGMC). The damage extent of the detail fatigue cracking is determined by crack exceedance probability.In general, the engineering approach is applied to other structure details such as cutouts, fillets, lugs, etc.A number of tests were conducted and a calculation program for optimizing the parameters were written. By comparing the test results with the calculation results, it is demonstrated that the approsch is suitable for durability analysis of aeronautic structures.