割口单向复合材料的应力集中及强度问题研究

本文对含有中心割口的单向复合材料的细观应力集中和强度问题进行了研究。提出一种修正的剪滞模型，分析了割口前缘区域的基本为弹性和非弹性情形下的应力重新分布问题，从而得到了含有任意尺寸的割口前缘纤维的应力集中因子。在此基础上，采用细观统计破坏理论，分析了割口复合材料的拉抻强度。结果表明，应力集中因子及统计强度值均与实验结果接近。

STUDY OF THE STRESS CONCENTRATION AND STRENGTH FOR NOTCHED UNIDIRECTIONAL COMPOSITES

This paper investigates the microscopic stress concentration and thestrength for center notch unidirectional-composites. A modified shear-lag model isproposed and the stress redistributions in the intact fibers at root of a notch forboth elastic and nonelastic cases in the matrix at root of the notch is analysed,fromwhich the stress concentration factors in intact fibers at root of a notch of arbitrarysize are obtained. On the basis of the knowledge of these stress redistributions,thetensile strength of notched composites is analysed by using a statistical fracture theory. The predictions of the stress concentration factors and statistical strengthsshow very good agreement with the previous experimental results.