Issue 54

F. Benaoum et al, Frattura ed Integrità Strutturale, 54 (2020) 282-296; DOI: 10.3221/IGF-ESIS.54.20

(a) (b)

1000 1200 1400 1600 1800 2000

1000 1200 1400 1600 1800 2000

Witness beam a=35 With patch Lp=180mm a=35 With patch Lp=270mm a=35 With patch Lp=28mm

Witness beam a=35, ea = 2, ep=2, Lp=180 a=35, ea=2, ep=2, Lp=28 a=35, ea=1, ep=1, Lp=28 a=35 Without patch

Load [N]

0 200 400 600 800

Load[N]

0 200 400 600 800

0

1

2

3

4

5

6

7

8

9

0

2

4

6

8

10

Deflection [mm]

Deflection[mm]

Figure 4: Comparison of the load vs. mid-span deflection of: (a) effect of patch length L P , (b) effect of patch length L P and adhesive thickness.

(a)

(b)

10 20 30 40

a= 21 mm, Lp = 180 mm a= 35 mm, Lp = 180 mm a =35 mm, Lp = 270 mm

-40 -30 -20 -10 0

σ xy (MPa)

-140 -115 -90 -65 -40 -15 10 35 60 85 110 135

Normalized position ( x/Lp )

(c)

(d)

100 150 200 250 300

250

a =35 mm a= 21 mm a= 7 mm

Lp =270 mm Lp= 210 mm Lp = 180 mm

200

150

σ xx (MPa)

σ xx (MPa)

100

50

0 50

0

-140 -115 -90 -65 -40 -15 10 35 60 85 110 135

-100 -75 -50 -25 0 25 50 75 100

Normalized position ( x/Lp )

Normalized position ( x/Lp )

Figure 5: Evolution of interfacial Stresses along the bond line: (a) effect of patch length and adhesive thickness on the Von Mises stress, (b) effect of patch and crack lengths on the shear stress, (c) effect of crack length on the normal stress, (d) effect of patch length on the normal stress.

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