PSI - Issue 2_B

Jaime Planas et al. / Procedia Structural Integrity 2 (2016) 3676–3683 J. Planas et al. / Structural Integrity Procedia 00 (2016) 000–000

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Fig. 3. Definition of geometry (a) and softening law (b) for the three-point bent beam.

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68 128 Fig. 4. Meshes used for the three-point bent beam. The numbers refers to the approximate number of elements along the central cross-section.

Fig. 5. Nominal stress vs. bottom line extension.

The calculations have been carried out for D / 2 = 0 . 198 using the four meshes in Fig. 4 under control of bottom line extension ( w B -control, see Fig. 3). The main series of calculation reached the final value w B = 2 . 5 w 1 in 53 steps for all the meshes. Fig. 5 shows the resulting curves with colored markers; obviously, no spurious mesh sensitivity is detected. For the rougher mesh ( n = 16), calculations were also performed in which the final value was reached in 5 steps (crossed boxes in Fig. 5), and also in one single step. One can conclude that the calculations are insensitive to both mesh and step size, and that they are also extremely robust, since they came across a maximum without any trouble whatsoever.