PSI - Issue 7

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Stanislav Žák et al. / Procedia Structural Integrity 7 (2017) 254 – 261 Stanislav Žák et al. / Structural Integrity Procedia 00 (201 7 ) 000 – 000

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2. Description of applied models 2.1. The finite element model

Assessing the local values of SIFs on a very fine, micro-tortuous crack front is nearly impossible with standard fracture mechanics approaches. To obtain sufficiently precise results for CTS specimen loaded by the remote mode II loading a finite element (FE) model of this specimen was created.

Fig. 1. CTS specimen (dimensions and loading)

The CTS specimen with specific dimensions (Vojtek et al. (2016)) was used as a template for the FE model - see Fig. 1. To obtain enough accurate solutions in a relatively short computational time, the calculation procedures were divided into several steps. The first step was represented by a simple model of the CTS specimen containing a smooth crack with boundary conditions corresponding to a pure remote mode II loading. The second step consisted of a sub-model consisting of a small area embracing the notch tip and the crack faces. The small size of the sub model allowed us to use a much finer FE mesh, thus to model the effect of crack tortuosity precisely enough.