复合材料大斜削结构压缩试验和损伤模拟研究

Compressive Experiment and Damage Simulation Studies of Composite Structure with Plies Drop-off

对复合材料斜削结构进行了压缩试验和相应的有限元模拟分析,编制了损伤子程序模拟结构内部的损伤。通过对试验数据和数值模拟结果的对比,发现数值模拟结果和试验数据吻合较好。试验和模拟结果显示,由于削层的存在,使得结构更复杂,尤其在过渡段内,各截面的性能互不相同。通过损伤模拟,预测了三种损伤形式的萌生位置和扩展方向,发现结构同时发生基体开裂损伤和纤维-基体剪切损伤,然后再发生纤维屈曲损伤。基体开裂损伤和纤维-基体剪切损伤的发生对结构的承载能力有严重影响,是灾难性的。而随后发生的纤维屈曲损伤加剧了这种影响,此时结构完全失去承载能力。

Composite structure with plies drop-off is studied by compressive experiment and FEM. A user subroutine is implemented to ABAQUS to simulate the damage of structure. The simulation results agree well with experimental data. The experimental data and FEM simulation results show that the composite structure with plies drop-off is very complex. Especially in the transition segment, the properties of every section are different. At damage simulation, the initiation and development of three types of damage are predicted. The matrix cracking damage and the shearing damage of fiber-matrix occur simultaneously at first, and then fiber buckling damage is founded. The effect of matrix cracking and fiber-matrix shearing is remarkable and catastrophic to the whole structure. Fiber buckling intensifies this effect, the initiation and development of fiber buckling indicates that the structure loses carrying capacity at all.