三维编织复合材料圆柱销剪切试验与数值模拟

复合材料紧固件连接技术是复合材料结构加工制造的关键技术之一,针对三维编织复合材料圆柱销紧固件的剪切性能进行了试验和有限元数值模拟分析。试件采用了三维全五向编织工艺进行制备。通过双剪性能测试得到了三维编织复合材料圆柱销的极限承载能力和破坏断裂形式,采用均匀化方法对圆柱销试件的宏观弹性常数进行了预测,采用改进后的Tsai-Hill准则并引入连续介质损伤力学建立了一套三维编织复合材料强度分析方法,并根据该方法对圆柱销试件在剪切载荷作用下的渐进失效破坏过程进行了有限元分析,计算结果与试验结果具有良好的一致性,表明提出的强度分析方法在预测三维编织复合材料结构件的宏观强度性能方面是有效可行的。

Test and numerical simulation on shear property of 3D braided composite straight pin

Joining technique using composite fasteners is one of the key technologies for the manufacturing of composite structures. Test and numerical research on the shear property of 3D braided composite straight pin fastener is presented. Three-dimensional full five-directional braided technology is used to fabricate the specimens. The shear tests of the specimens are preformed to study the ultimate bearing capacity and failure style of the 3D braided composite straight pin. A homogenization method is used to predict the elastic constants of the straight pin specimens. A strength analysis method is established to describe the strength characteristics of the 3D braided composite straight pin specimens. The modified Tsai-Hill failure criterion and continuum damage theory are introduced into the method. According to this method, a finite element model is developed to simulate the progressive damage process of the specimens. Good agreements are achieved in the load-deflection curves and damage distributions between test and numerical results under shear load, indicating that the proposed analysis method is effective and feasible in predicting the macroscopic strength of 3D braided composite structures.