非線形き裂力学のV型切欠き強度評価への適応

抄録

In this study, the non-linear crack mechanics proposed by Prof. Nisitani is applied to the strength evaluation of V-shaped notch plate under large scale yielding condition. The tensile test of carbon steel JIS S45C specimen is carried out to obtain failure stress for various notch depths and angles. The value of plastic strain at the notch-tip-node in the specimen is computed by elastic-plastic FEM analysis under the same mesh pattern. As a result, it is found that the failure strength of the sharp notched specimens for various notch depths and angles can be estimated by using the plastic strain at the notch tip calculated by FEM. In addition, the plastic singularity index of V-shaped notch can be obtained by a simple analysis using the finite element method. The Mode I and Mode II indices of plastic stress singularity can be easily obtained under tension and shear loading conditions.