PSI - Issue 36

O. Kononchuк et al. / Procedia Structural Integrity 36 (2022) 177–181 O. Kononchu к , V. Iasnii, N. Lutsyk / Structural Integrity Procedia 00 (2021) 000 – 000

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Fig. 3. Strain distribution along the OX axis of the beam strengthened y carbon fibre tape, the bending moment М = 4.03 kN  m.

a)

b)

Fig. 4. The relationship between bending moment and strain of the strengthened RC beams defined experimentally and by FEM: а) primary reinforcing bars and b) external composite material.

The numerical method allows obtaining not only the value of strength characteristics of the structure, but also represents the ability of their propagation. Sufficient accuracy of crack initiation and propagation on each loading step was provided by using 3-dimensional finite element SOLID65. Fig. 5 shows a grid of cracks after experimental testing (Fig. 5a) and obtained by modelling (Fig. 5b). There is a good match of the geometries of the cracks at losing the load-bearing capacity of the beam. The main crack occurs while cracks merging under tension (propagate underneath) and compression (propagate uppermost). The region of cracks merging could be clear seen on the Fig. 5.