金属和复合材料多钉连接钉载分配研究

Study on Load Distribution of Multiple-bolted Metal to Composite Joints

本文针对金属-复合材料多钉连接件的载荷分布进行试验研究和数值分析。首先,通过应变电测法测量了一列三螺栓双剪连接件的钉载分配比例,揭示出该比例随载荷变化的现象和特征。然后,建立了考虑多面接触的三维实体有限元模型,在计算分析中考察钉-孔间隙分布、预紧力和摩擦对钉载分配的影响规律。计算结果表明:初始间隙是影响钉载分配比例的最重要的因素之一;通过改变初始间隙分布可以对试验中钉载分布的变化规律得出合理的解释;摩擦和预紧力对钉载分配比例的影响较小。

This paper deals with the load transfer and fastener load distribution of the multiple-bolted joints by means of the experimental study and finite element analysis.The specimens are the composites to titanium double lap joints with a column of three bolts.The fastener load distribution and the its alteration with external loading are determined in the experiments by the strain gauge measurement.Then the three-dimensional finite element model consisting of multiple contact interfaces is established.The effect of the factors,such as the interfacial friction,fastener preloading and the clearance between the bolt and hole on fastener load distribution are investigated.The calculation results indicate that the load ratios of different fasteners depend strongly on the magnitude of the external loading and the consistency of the initial multiple holes clearances.On the other hand,the effects of the interfacial friction and fastener preloading on the fastener load distribution are relatively small.