Abstract：The elastic-plastic fracture J- A2 method was performed to study the collinear two cracks in plate under biaxial load. By using finite element analysis, the fracture driving force J - integral and constraint parameter A2 of the main crack-front were calculated with different crack sizes and different dis- tances of cracks in biaxial load condition for different load ratios. As a comparison, the analysis result under uniaxial load condition was also presented. Results show that the constraint parameter A2 strongly depends on the tension that parallels with the crack, and the constraint increases with the tension when the J - integrals are the same. The constraint level of main crack-tip increases with the increasing length of the adjacent crack under uniaxial load condition, but it decreases with the increasing length of the ad- jacent crack under biaxial load condition. The constraint level of main crack-tip decreases with the increasing distance of the cracks under all load conditions.
2009, Vol. 30 
