本文所探讨的问题,由于复杂和困难,虽经过许多学者数十年的研究,取得了重大的进展,但至今还未很好解决。我们对各种简化假定的合理性、不同计算模型的差别以及不同计算方法的影响等作了简要的探讨。对前人的工作略加评述。对常见公式的适用性提出一些看法。对一些现象的机理作了解释。给出了有一定的理论背景和实验依据的半经验公式,可适用于各种纤维增强聚合物基体复合材料。 Due to its complexity and difficulty, the issues discussed in this article have made great progress despite decades of research by many scholars, but so far they have not been solved yet. We briefly discuss the rationality of various simplifying assumptions, the differences between different calculation models and the influence of different calculation methods. A little comment on the work of predecessors. Some comments on the applicability of common formulas. The mechanism of some phenomena is explained. A semi-empirical formula with a certain theoretical background and experimental basis is given, which can be applied to various fiber-reinforced polymer matrix composites.