含孔边套筒的厚截面复合材料接头耳片强度分析

Analyzing Thick-Section Composites Lug with Hole Containing Boundary Sleeve

为研究含孔边防护套筒的厚截面复合材料层合板耳片连接件孔边层间应力分布规律及接头强度,提出了采用层合板子层和界面胶层相结合的有限元建模方法,在验证了建模方法对厚截面层合板应力求解的有效性的基础上,分析了承受轴向载荷的厚层合板耳片连接件孔边三维应力分布及接头失效情况。结果表明:套筒胶层的破坏应力和破坏位置主要集中在孔轴非接触区;当套筒胶层发生断裂时,厚截面层合板并未发生失效,限制了厚板接头耳片整体强度性能的提高。

A finite element（FE） modeling method with cohesive interface and sublaminates was proposed to study interlaminar stress distribution and strength of thick-section composite materials lug. And numerical calculation was carried out on the thick composite laminates three-point bending problem; effectiveness of modeling method for thick-section composite materials stress calculation was verified, Based on this, a three dimensional（3D） FE model of thick-section composite materials lug is designed; then the 3D stress distribution along the hole edge and failure mode of the lug subjected to axial load are discussed. The results and their analysis show preliminarily that ： （ 1 ） the failure stress and damage position are mainly concentrated in the no contact region of the hole-axis; stiffer metal sleeves reduce the interlaminar stress concentrations of hole edge, however, this and higher radial tensile stresses in the region lead to reduced carrying capacity of the sleeves adhesive; （2） the adhesive of sleeves fails before the thick-section composites lug; this destroyed the integrity of the protective structure and will adversely affect the strength of the thick-section composites lug.