Abstract
There are a lot of schemes for predicting long-term durability of composite materials. As the scheme becomes complicated, the prediction would be precise whereas the prediction needs more numbers of constants. If many of parameters are needed, in fact there is a case it is difficult to predict that because the acquaintance of all of them is almost impossible. A numerous number of constant hinders us to apply the scheme ; but when the number of constant is smaller, more of us can apply the model, i.e. easy to use. The simultaneous fiber failure (SFF) model presented by Koyanagi et al only needs small number of constants ; about ten constants are needed for predicting long-term durability precisely. The number might be however still much compared with kinetic crack growth (KCG) theory presented by Christensen, which does not model actual composite failure mechanism. The consistency between SFF and KCG is discussed in this paper. If KCG works well, KCG is better to apply for predicting longterm durability because necessary constants are less. This paper introduces the two models and then compares them.
