含中心裂纹有限加筋板应力强度因子理论及数值仿真分析

Theoretical Analysis and Numerical Simulation of Stress Intensity Factor for Stiffened Plates with Central Crack

基于裂纹问题的复变应力函数、Paris位移公式和变分原理对板材和筋条均含裂纹的加筋板结构的应力强度因子进行了分析求解。对加筋板离散化,忽略受拉时筋、板弯曲的影响,将筋条对裂纹板的作用力转化为作用在板的节点剪力,从而求解了含裂纹加筋板的问题。采用数值仿真方法分析了应力强度因子随板材和加筋条上裂纹扩展的变化规律,研究了加筋条刚度和加筋条间距变化对裂尖处应力强度因子的影响。

The object of this paper is to develop a method to determine the stress intensity factor for ship stiffened plate subjected to correlated cracks in the stiffener and plate elements. The Paris displacement formula, the complex stress function and the variation principle are applied to analyze fracture linear elastic of ship stiffened panels. The bending effect is neglected in the investigation, and it is assumed that the tangential traction along two sides of the cracked plate is converted into sheer force of stiffener, and then the final solution is obtained. At the same time, the stress intensity factor calculated by finite element analysis is analyzed in the paper, accounting for the effect of stiffener＇s stiffness and spacing changes.