带环状裂纹圆棒的J积分评价方法

通过有限元解析方法分别研究了轴向或扭转载荷下带环状裂纹圆棒试样的J积分的评价方法。首先模拟计算得到了一系列带有不同深度环状裂纹的中碳钢圆棒试样的载荷-位移关系,然后分别利用单试样的简单评价法和多试样的能量评价法计算J积分值。结果发现,当圆棒试样的裂纹深度足够深或位移足够小时,两种评价方法计算的J积分值相当一致。

An Investigation of J Integral Evaluation Method for Cylindrical Bars with Circumferential Crack

Finite element method was used to analyze the J integral evaluation method for a cylindrical specimen with deep circumferential crack under axial or torsional load.First,the relationship between axial or torsional load and axial or angular displacement of cylindrical specimens with different circumferential crack depth was determined.Then,two methods were used to calculate the J integral.One is the simple method that calculates the J integral by a single specimen's load-displacement relationship;the other is the energy method.The J integral obtained by the simple method agrees well with that determined by the energy method using multiple medium carbon steel specimens with a circumferential crack,as far as the crack depth is deep enough or the axial or angular displacement is small.