Modeling of Mixed Mode Fracture Tests Using Extended Finite Element Method

Authors

1 PhD Student, Mech. Eng., K.N. Toosi Univ of Tech., Tehran, Iran

2 Prof., Mech. Eng., K.N. Toosi Univ of Tech., Tehran, Iran

Abstract

In the present study, a mixed mode fracture specimen was simulated by the extended finite element method. For this, a specimen called "Diagonally loaded square plate" was selected. For this specimen, experimental test results are available. The loading process including the fracture and crack growth is simulated. Displacement control loading is considered. The crack growth increment and direction are determined using the fracture criteria. Various test specimens are simulated using a model with the fixed mesh. Therefore, computation costs has decreased dramatically. Furthermore, numerical integration in the enriched elements is studied and the optimum number of gauss points in these elements are determinrd. Comparing the results of the extended finite element method with the experimental data show that the critical fracture load and the stress intensity factors at the fracture moment differ less than 10%. Furthermore, there is a convincing agreement between the crack growth path in the experimental test results and numerical analysis by the extended finite element method.

Keywords

Main Subjects


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