复合材料单螺栓双剪搭接干涉配合疲劳强度评价

该文采用有限元软件ANSYS,建立了复合材料单螺栓双剪搭接干涉配合的三维有限元模型,研究了当连接模型中施加了预紧力时,预紧力对干涉配合的影响.首先分析了无载荷作用下复合材料板在干涉配合孔边切向应力分布特点;之后比较了双剪搭接在10kN 和15kN 两种远程纵向载荷作用下,孔边切向应力的分布情况.结果表明:远程纵向循环载荷作用下,预紧力能有效均匀各板所受载荷,并可消除在无预紧力时中板上的局部应力集中点,而且适当增大预紧力能提高干涉配合连接的效率;此外研究显示双剪搭接连接在不同的载荷下,疲劳危险点也不同;最后研究了复合材料干涉配合连接时,各板的交叉区域孔边切向应力分布,因此得出各板在高低不同的载荷下疲劳危险点的分布.

FATIGUE STRENGTH ASSESSMENT OF AN INTERFERENCE FIT OF SINGLE-BOLT,DOUBLE SHEAR LAP COMPOSITE BOLTED JOINTS

A three dimensional finite element model of single-bolt, double shear lap composite bolted joints was established through engineering software ANSYS. In order to investigate the effect of preload, the preload was exerted to the bolted joints in the model, and then the tangential stress at the edge of the hole of composite laminates was analyzed. The resultant tangential stresses at the edge of the hole were compared between two cases: under high and low longitudinal remote cyclic tensile loadings. The results show that, the tangential stress is balanced by the effect of bolt preload, which can eliminate the localized stress concentration on the middle plate and improve the efficiency of the joints under the remote loadings. Moreover, the research proves that different remote loads lead to different dangerous points of fatigue. Finally, the tangential stress at the hole edge of the cross area in composite interference fit joints was analyzed, and the distributions of dangerous fatigue points on each plate were obtained.