引張り-ねじり二軸組合せ荷重下における平織りガラス布強化複合材料の疲労寿命予測

抄録

Fatigue degradation and life prediction for a plain woven glass fabric reinforced polyester under tension-torsion biaxial loading were investigated. A fatigue damage accumulation model based on the continuum damage mechanics theory was developed, where modulus decay ratios in tension and shear were used as indicators of damage variables (D). In the model, the damage variables are considered to be second-order tensors. Then, the maximum principal damage variable, D^* is introduced. According to the similarity to the principal maximum stress, D^* is obtained as the maximum eigenvalue of damage tensor [D^'_<ij>]. Under proportional tension-torsion loading, fatigue lives were satisfactorily predicted at any biaxial stress ratios using the present model in which the fatigue characteristics only under uniaxial tension and pure torsion loadings were required.