论文部分内容阅读
复杂焊接残余应力场作用下的应力强度因子是焊接结构损伤容限分析的前提。权函数法是求解任意载荷下应力强度因子的高效手段,但裂纹几何的复杂性给经典权函数法的应用带来了障碍。本文利用一种新的基于复变函数泰勒级数展开的权函数解法,通过复变有限元计算,求解裂纹面位移对裂纹长度的偏导数,采用经典权函数的级数展开式作拟合,确定无限大板周期性共线裂纹、有限宽板中心裂纹以及有限宽板单边裂纹的权函数,并确定了这3类裂纹在典型焊接残余应力作用下的应力强度因子。与经典权函数法、有限元法以及有关文献结果的广泛对比表明,基于复变函数泰勒级数展开的权函数法,为包括焊接残余应力的复杂载荷条件下的裂纹问题求解提供了高效高精度的手段。
The stress intensity factor under the effect of complex welding residual stress field is the prerequisite for damage tolerance analysis of welded structures. The weight function method is an efficient method to solve the stress intensity factor under arbitrary load, but the complexity of the crack geometry brings obstacles to the application of the classical weight function method. In this paper, a new weight function method based on the Taylor series expansion of complex functions is used to solve the partial derivative of the crack length by crack transformation with complex finite element method. The series expansion of the classical weight function is used for fitting. The weight function of periodic crack, infinite crack center crack and single crack crack of infinite wide slab are determined, and the stress intensity factors of these three kinds of crack under typical welding residual stress are determined. Extensive comparison with classical weight function method, finite element method and related literature results shows that the weight function method based on the Taylor series expansion with complex functions provides high efficiency and high precision for solving crack problems under complicated loading conditions including welding residual stress s method.