A Semi-elliptical Crack Modeling and Fracture Constraint on Failure Diagram

Modeling the semi-elliptical crack with the ‘in-house’ capability of finite element tool is the first challenge of this work. In spite many effective schemes had been found their systematic processes are still not openly published. Beside, almost all the schemes were using the complicated-external grid generator. On the other hand, predicting the fracture toughness under constraint condition is another challenging subject. Failure assessment based on constraint parameter is also needed to further study particularly in semi-elliptical crack problem. In this paper, the effective meshing and modeling scheme of semi-elliptical crack was firstly developed using simple sweep strategy. Convergence study and evaluation of the scheme are conducted. Then, specific modeling scheme is finally proposed. The constraint parameter fracture mechanic was reviewed in detail. The construction of failure assessment diagram based on this constraint parameter is then reconsidered. Both subjects are needed to produce the alternative mode in the designing and assessing the structural integrity.