无传载紧固孔的疲劳寿命估算

本文根据紧固件与紧固孔的间隙配合、平滑配合或干涉配合情况具有的不同接触应力和干涉应力、应变分析特点,研究了用Neuber方程分析孔边局部应力、应变等循环参数和用Manson-Coffio应变疲劳寿命方程估算无传载紧固孔的痨劳寿命方法。例举的紧固件与紧固孔不同配合试验件的疲劳寿命试验结果与本文利用应力严重系数法分别计算的结果对比表明,本文所述的无传载紧固孔疲劳寿命估算方法与试验结果是比较一致的。这一循环参数分析和疲劳寿命估算方法为典型机翼下壁板结构的疲劳寿命估算建立了基础。

Fatigue Life Estimation of Fastener Holes without Load Transfer

Based on the different characteristics of contact stress, interferential stress and strain distribution between fasteners and fastener holes of clearance, neat and interferential fit, analysis of cyclic parameters of stress and strain is studied with Neuber equation, and the fatigue life of fastener holes without load transfer is estimated with Manson-Coffin strain fatigue equation. As an example, the test result of fatigue life of different fitting specimens of fasteners and fastener holes is compared with the result of this paper and the stress severity factor method, showing that the fatigue life estimation of fastener holes without load transfer, as stated in this paper, is comparable and in good agreement with the test result. Through the cyclic parameter analysis and the method of fatigue life estimation, a basis for fatigue life estimation of typical lower-wing structure is established.