【摘要】 论文将使用一种界面单元来解决二维裂纹的静态扩展问题.这种界面单元基于虚拟裂纹闭合法,利用商业有限元软件ABAQUS的用户自定义单元UEL功能,发展为界面断裂单元,计算应变能释放率(GⅠ和GⅡ).在裂纹尖端的两个节点间设置一个特殊刚度的弹簧,并引入哑节点计算裂纹尖端后面的张开位移和裂纹尖端前面的虚拟裂纹扩展量.采用这种单元计算应变能释放率时不需要使用奇异单元或折叠单元,不会出现收敛问题,也不需要复杂的后续处理.因此,采用这种断裂单元分析二维裂纹扩展问题是方便的、高效率的,而且也能得到可靠的精度.更多还原

【Abstract】 This paper introduces an element to deal with 2D progressive crack growth problems.An interface element was developed to calculate the strain energy release rates based on the virtual crack closure technique(VCCT) using commercial FEA software ABAQUS with the user defined element(UEL).A very stiff spring is placed between the node pair at the crack tip to calculate the internal forces and dummy nodes are introduced to extract information for displacement openings behind the crack tip and the virtual crack jump ahead of the crack tip.No the special singularity element,the collapsed element,extra post-processing and convergence difficulty is required for interface element to use calculate the strain energy release rates.Therefore,the interface element for VCCT using to calculate the strain energy release rates is simple,efficient and reliable precision in analyzing 2D crack growth problems.更多还原