含表面缺口复合材料层压板的屈曲破坏

通过实验研究和理论分析探讨了含表面缺口复合材料层压板的屈曲破坏。采用电测和声发射技术对层压板的受压力学行为进行观测和分析。作为比较,对无缺口层压板也进行了压缩试验,尽管2种层压板试样随载荷增加到一定值时都会发生屈曲,但它们的破坏过程仍有着显著的差别。利用层压板刚度减少技术推导了含表面缺口复合材料层压板的临界应力表达式。理论预测结果和试验结果能够较好地吻合。

COMPRESSIVE BUCKLING FAILURE OF LAMINATES WITH A SURFACE NOTCH

The buckling failure of composite laminates with a surface notch is explored through experiments and analysis. Both strain gauge and acoustic emission techniques are used to observe the mechanical behavior of the laminates with increasing load. For comparison, the unnotched laminate coupons are also tested. Although both notched and unnotched coupons fail in the mode of buckling, there are still some apparent differences in the features of the failure process. A simplified expression for calculating the critical stress is developed according to a stiffness reduction technique. The experimental and theoretical results show good agreement.