十字叠层梁冲击损伤的有限元模拟

FEM SIMULATION ON IMPACT DAMAGE OF CROSS-PLY LAMINATED BEAM

对一类十字叠层梁的冲击损伤机理与演化进行了有限元模拟。按实际叠层结构计算应力分布，根据破坏理论预测了损伤的萌生、位置与模式，并用“损伤材料刚度衰减原理”模拟损伤演化。结果表明，早期损伤以层间剪切为主导，而后将与９０°层基体开裂发生互耦作用，最危险的位置是三点弯曲加载点和支撑点。计算了因损伤造成的弯曲刚度下降，与试验结果相符。此外，还定性地分析了损伤的稳态扩展与失稳扩展。

Finite element method(FEM )simulation on damage evolution of cross plylaminated beam specimen subjected to transverse impact is presented.The actual laminationconstruction and real specimen configuration were considered in dividing the finite elementmesh pattern. Stress distribution in each layer was calculated.Damage initiation,mode andlocation of the first damage event were predicted by using failure theories.The results showthat the interlaminar shear delamination failure is the dominant damage mode and it is apt tocouple with the matrix cracking in 90°layers, The loading point and supporting points arethe most dangerous locations in the earlier damage stage. The well-known principle ofdegradation of elastic properties of damaged material was used to simulate damage evolution.The stable and unstable extension of the damage zone estimated in the paper mayqualitatively explain the multiple fracture in impact tests. The decrease of bending stiffnessof the specimen with damage growth was also calculated and compared favourably with theexperimental data.