复合材料层合板的低速冲击损伤及其剩余压缩强度研究

THE RESEARCHES ON LOW VELOCITY IMPACT DAMAGE AND RESIDUAL COMPRESSIVE STRENGTH OF COMPOSITE LAMINATES

本文采用理论和实验方法研究了复合材料层合板的低速冲击损伤及其剩余压缩强度．文中利用有限元方法和能量转换原理计算了层合板受到低速冲击时的受载最危险状态，以及此时的应力分布．并用Ｔｓａｉ－Ｗｕ张量准则判断损伤情况，对产生损伤的单元进行相应的刚度折减，且作重复计算直至不产生新的损伤为止．最后，对受到冲击的层合板还进行了剩余压缩强度计算．在实验中，采用激光全息无损检测法测量了层合板的冲击损伤，并对受冲击的层合板进行了剩余压缩强度测量．理论值和实验值相吻合．

In this paper, the low velocity impact damage and the residual compressive strength of composite laminates were analyzed by using theoretical and experimental methods. The finite element method and the energy conservation principle were used to calculate the most critical loading state in the impact processes and the stress distributions at tnts time. The Ply failure region was calculated by the Tsai-Wu criterion, and reduced elastic moduli were then used in the failure region in subsequent step by step calculation until no new damage appeared. Then the residual compressive strength of composite laminates subjected to low velocity impact was calculated. In tests, the interior impact damage was determined by holographic nondestructive testing, and the residual compressive strength of laminates subjected to impsct was determined also. The theoretical values are good agreement with that of experiment.