PSI - Issue 42

Zeng Chen et al. / Procedia Structural Integrity 42 (2022) 180–188 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

183

4

3. Numerical modelling Finite element analysis (FEA) was conducted with ABAQUS 6.14. Considering symmetry condition, one-quarter C(T), SEN(B), cruciform and rectangular specimen models with the same sizes as the tested specimens were created, which are shown in Figure 4 . The Young’s modulus and Poisson’s ratio are 204.3GPa and 0.3 respectively (Van Gelderen, 2016). The true stress – strain curve is in Figure 3.

Figure 3. True stress – strain curve of BS1501-224 28B steel at - 160℃ (Van Gelderen, 2016).

8-noded quadratic elements with reduced integration (C3D8R) were applied. The sharp crack tips were applied in all the specimens to simulate the fatigue pre-cracks. As shown in Figure 5, a highly refined and focused mesh was established around the crack tip to raise the accuracy of the simulation outputs. For all models, the load rollers and support rollers were created as rigid bodies. The contact condition between the rollers and the specimens was defined as surface-to-surface contact with a finite-sliding formulation. All simulations were conducted by applying a load-line displacement V LL to the load roller.

Load

Symmetry plane

W=10mm

Crack surface

a =5mm ( a/W =0.5)

27.5mm (Half length)

(a)

5mm (Half thickness)

Symmetry plane

Load

Crack surface

Symmetry plane

12.5mm (Half thicknes s)

W=50mm

a =25mm ( a/W =0.5)

30mm

(b)

62.5mm

Symmetry plane