PREDICTION OF SINGLE SIDE CRACK FATIGUE GROWTH IN CFRP STRAPS BASED ON THE BOUNDARY COLLOCATION METHOD AND STRESS INTENSITY FACTOR

Based on the Boundary Collocation method, the stress intensity factors corresponding to different fatigue crack lengths of CFRP straps under axial tensile loading of single edge crack were deduced and calculated. Based on the results of fatigue experiment, the curved interface region of CFRP ring was selected for local analysis, and the crack length under different loads was calculated according to the fracture toughness. Based on the calculation results of the failure length of fatigue crack, the famous relation of crack growth law, Paris formula, was used to establish the functional relation between the fatigue crack length and the cycle times of CFRP ring, a highly orthotropic material, and the prediction curve of crack growth under a certain stress load was obtained.