Li Shu, Han Fei
Department of Mechanical and Electrical Engineering, North China University of Technology, Beijing 100144, China.
Materials (Basel). 2022 Mar 17;15(6):2227. doi: 10.3390/ma15062227.
In this paper, a failure theory for the multidirectional fiber-reinforced composite laminate with a circular hole is developed. In this theory, the finite fracture mechanics method is combined with the improved Puck's failure theory including the in situ strength effect. It can predict the notched strength by only basic material properties of unidirectional laminas, geometries and stacking sequence of the laminate. In advance mechanical properties of the laminate are unnecessary. The notched laminates with different material types and stacking sequences are taken as examples to verify this failure theory, and predicted results are in good agreement with experiments. Based on the developed failure theory, importance measurement of uncertain material properties to the notched strength is analysed. Results show that notched strength increases with increasing longitudinal tensile strength and in-plane shear modulus for the laminate with an arbitrary hole diameter. However, it decreases with increasing transverse modulus.
本文提出了一种含圆孔的多向纤维增强复合层合板的失效理论。该理论将有限断裂力学方法与考虑原位强度效应的改进型普克失效理论相结合。它仅通过单向层板的基本材料性能、层合板的几何形状和铺层顺序就能预测缺口强度。无需预先知道层合板的力学性能。以不同材料类型和铺层顺序的缺口层合板为例对该失效理论进行验证，预测结果与实验结果吻合良好。基于所提出的失效理论，分析了不确定材料性能对缺口强度的重要性度量。结果表明，对于任意孔径的层合板，缺口强度随纵向拉伸强度和面内剪切模量的增加而增大。然而，它随横向模量的增加而减小。
