复合材料圆柱壳的轴压屈曲失效试验

为了研究高径比大于1的复合材料圆柱壳的轴压屈曲性能及其失效模式,对2组单向纤维圆柱壳和3组外侧环裹环向纤维圆柱壳进行了轴压试验,观察了试件的受力过程和破坏形态,获得了荷载-位移曲线和荷载-应变曲线,利用有限元模型分析了单向纤维圆柱壳两种屈曲形式的破坏机制,对比分析了两种铺层试件的轴压性能。结果表明:单向纤维复合材料圆柱壳出现先纵向劈裂后板壳屈曲和先柱壳屈曲后纵向劈裂的两种破坏模式;外侧环向纤维可改善圆柱壳的轴压性能,屈曲发展有一定的阶段性并表现出延性特征,破坏形式和承载力均较为稳定。

Experiments on the buckling behavior of composite cylindrical shells subject to axial compression

In order to study the buckling behavior and failure model of composite cylindrical shell with aspect ratio greater than 1 subject to axial compression, the axial compression tests for two unidirectional fiber composite cylindrical shells and three composite cylindrical shells wrapped hoop fiber were conducted, respectively.The failure model, load-displacement relationship and load-strain relationship were documented during the loading process.Then, the failure mechanisms of two unidirectional fiber composite cylindrical shells were numerical analyzed and the axial compression behaviors of those two shells were comparative analyzed.The results show that there are two failure models for unidirectional fiber composite cylindrical shell under axial compression: the longitudinal splitting of cylindrical shell followed by the buckling of each plates, or the buckling of the cylindrical shell followed by the longitudinal splitting;the outer hoop fibers can improve the behavior of cylindrical shells under axial compression, and the buckling process has certain stages showing that ductile characteristics and stable carrying capacity and failure modes.