As an important covariate for assessing whether cracks are extended or not,the accuracy of the calculation of the stress intensity factor affects the assessment of material properties.The stress intensity factor at the crack tip was calculated by four numerical cases of a three-point bending beam containing precast cracks,rectangular slab center crack,rectangular slab center oblique crack,and rectangular slab center interface crack models using displacement extrapolation method and extended finite element method,respectively.The computational accuracy of the two methods was verified by comparing the computational results with the analytical solutions or reference solutions of other numerical methods.In addition,the effect of grid density on the accuracy of the stress intensity factor solution and the effect of eliminating the results near the crack tip on the displacement extrapolation method to solve the stress intensity factor was discussed.It is found that the displacement extrapolation method can improve the accuracy by local encryption of the crack tip and removal of the crack tip singularities.The extended finite element method requires a relatively small mesh density,and the mesh density can be increased appropriately considering the comprehensive calculation time.The results can provide a reference for solving the stress intensity factor and calculating the fracture toughness for the experimental-numerical coupling method.
关键词
应力强度因子/位移外推法/扩展有限元法/单材料均质模型/双材料界面模型
Key words
stress intensity factor/displacement extrapolation method/extended finite element method/single-material homogeneous model/two-material interface model
维普
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