复合材料层板基于剩余刚度比的剩余强度模型

本文从唯裂 学的观点提出了一个复合材料疲劳剩余刚度衰退模型，根据该模型导出了基于疲劳乘余刚度比的复合材料层合板疲劳剩余强度概率分布模型，给出了确定该模型中各参数的计算方法，根据该模型可预报复合材料层合板在某一应力水平的疲劳载荷作用下疲劳剩余刚度比为某一确定值时的疲劳剩余强度概率分布。为验证该模型的合理性，用典型复合材料层合板做了几组疲劳实验，并用实验数据对模型中的参数进行了估计，计算结果证明，该模型预报的疲劳剩余强度概率理论分布与实验结果符合较好。

A Fatigue Residual Strength Model for Composite Laminates Based on Residual Stiffness Ratio

From the phenomena of stiffness degradation of composite laminates under fatigue loads, this paper presents a model of stiffness degradation for composite laminates. On the basis of this model and a cycles-based model of fatigue strength degradation for composite laminates, a probability distribution model of fatigue strength degradation, which is based on the ratio of initial stiffness to residual stiffness, for composite laminates was derived and a methodology was given for determination of the parameters in the model. By using this model, the probability distribution of residual strength can be predicted when the ratio of fatigue residual stiffness is equal to some value under some stress level. Several group of fatigue experiment were made for the proofing of this model with typical composite laminates and the model parameters were determined from the experimental data. It is shown that the theoretical prediction of probability distribution of residual strength with this model has good coincidence with the experimental results.