A New Fatigue Residual Stiffness Statistical Distribution Model for Composite Laminates
Feng Peifeng(1), Wang Dianfu(2), Du Shanyi(2), Li Haitao(2)
(1,Jimei University Xiamen 361021) (2,Harbin Institute of Technology Harbing 150001)

Abstract: Based on the analysis of the existing models on the stiffness degradation of composite laminates and from the phenomena of stiffness degradation of composite laminates under fatigue loads, a new and more reasonable statistical distribution model of the fatigue residual stiffness for composite laminates has been derived, which relates the stiffness degradation to the fatigue cycles. In the paper, the procedure is given for determination of the parameters in the model. By the use of this model, the statistical distribution of the residual stiffness of composite laminates can be predicted when the fatigue cycles are given. A experimental test program has been conducted to generate meaningful data for verification with typical composite laminates and the parameters in the model are estimated by using the experimental data in the proposed parameters procedure. It is shown that the correlation between the theoretical predictions on the residual stiffness statistical distribution and the experimental results is outstanding.
Keywords: composite laminates, residual stiffness, fatigue, statistical distribution.