加强筋对三维裂纹应力强度因子的影响

Effect of Reinforcing Bars to the Stress Intensity Factors of Three Dimensional Crack

对含有表面裂纹的构件,采用加强筋进行局部加强可以阻止或延缓裂纹的扩展。应力强度因子是表征裂纹尖端应力应变场的重要参量,因此研究加强筋对表面裂纹应力强度因子的影响对于加强筋的设计具有十分重要的意义。运用断裂力学的理论,采用有限元分析方法,建立带加强筋的平板表面裂纹三维模型。在裂纹长度不同的情况下,以加强筋的位置、长度、宽度和厚度为参数,分析了不同参数对裂纹应力强度因子的影响。结果表明,应力强度因子与加强筋的位置、宽度及厚度有关,长度对其影响可以忽略。

For the components containing surface crack ,the use of reinforcing bars for local strengthening can prevent or delay the extension of crack. Stress intensity factor is an important parameter to characterize the stress and strain field of the crack tip. Therefore ,studying the effect of reinforcing bars on stress intensity factor of surface crack has very important significance for reinforcement design. It establishes the three dimensional model of a plate surface crack with reinforcing bars by using the theory of fracture mechanics and the finite element analysis method. In the case of different crack length,the influence of different parameters on the stress intensity factors of crack is analyzed varying the geometrical parameters including the position,length,width and thickness of the reinforcing bars. The results show that stress intensity factor has a relation with location,width,thickness of reinforcing bars ,and the influence of length on the stress intensity factor can be neglected.