含裂纹功能梯度板能量释放率的ABAQUS用户子程序开发

ABAQUS User Subroutine Development for Energy Releasing Rate of the Functionally Graded Plate with Cracks

为求解含裂纹功能梯度板的动态能量释放率,提出了基于非均匀有限元法的虚拟裂纹闭合法.基于有限元软件ABAQUS平台,开发了动态载荷作用下功能梯度材质的哑节点断裂单元,编写了用户自定义子程序UMAT和UEL,求解了动态载荷作用下的含裂纹功能梯度板能量释放率分量.对不同形状因子下的中心和倾斜裂纹功能梯度板的动态能量释放率分量进行了求解,并转化为动态应力强度因子,与差分法作比较.数值算例结果表明,动态载荷作用下功能梯度材质的哑节点断裂单元具有精度高、简捷方便、裂尖无需使用奇异元或特殊单元和子程序通用性强等优点,为工程师求解动态断裂参数提供了新途径.

To obtain the dynamic energy releasing rate of the functionally graded plate with cracks, a virtual crack closure technique was proposed based on the inhomogeneous finite element method. A fracture dummy node element of the functionally graded material under dynamic loading was developed, user-defined subroutines named UMAT and UEL were programmed, and the component of energy releasing rate for the functionally graded plate caused by dynamic loading was calculated based on the finite element software ABAQUS platform. For the different shape factors such as the center-crack and inclined-crack inside the functionally graded plates, the component of the dynamic energy releasing rate was solved, and then it was transformed into the dynamic stress intensity factor, which was used for comparing the results calculated by the finite difference method. The numerical calculating results showed that the dummy node element of the functionally graded material fracture caused by dynamic loading is characterized by high precision, simplicity and convenience without using the singular element or special element for the crack tip and the versatility of its subroutines, which may provide a new approach for the engineers to get the dynamic fracture parameters.