Issue 51

G. Ramaglia et alii, Frattura ed Integrità Strutturale, 51 (2020) 288-312; DOI: 10.3221/IGF-ESIS.51.23

ID specimen b [mm] d [mm] h [mm] Type of fiber [-] n l

[-] t eq

[mm] f mc

[MPa] f m0

[MPa] f mc

/f mc0 1.604 1.372 1.817 1.673 1.580 1.640

[-]

S18 S19 S20 S21 S22 S23

264 267 266 266 265 265

265 265 265 266 264 264

560 560 560 560 560 560

Glass Glass Glass Basalt Basalt Basalt

1 1 1 1 1 1

0.48 0.48 0.48 0.24 0.24 0.24

9.97 8.53

6.22 6.22 6.22 6.22 6.22 6.22

11.29 10.40

9.82

10.20

Table 3.B : Geometrical characteristics and experimental results [34].

k eff [-]

f l,(eq.13) [MPa]

f l,eff,(eq.13) [MPa]

(f l,eff

/ f m0

), (eq.13)

f l, (eq.18) [MPa]

f l,eff, (eq.18) [MPa]

(f l,eff

/ f m0

), (eq.18)

ID specimen

[MPa] 0.399 0.395 0.397 0.225 0.226 0.226

[MPa] 0.399 0.397 0.398 0.225 0.226

S18 S19 S20 S21 S22 S23

2.48 2.46 2.47 1.40 1.40 1.40

5.80 5.75 5.77 3.27 3.29 3.29

2.48 2.46 2.47 1.40 1.40 1.40

5.81 5.77 5.79 3.27 3.29 3.29

2.48 2.47 2.47 1.40 1.41 1.41

0.226 Table 4.B : Effective confining stress calculated according to Eqns. (13) and (18) for the experimental program, [34].

ID specimen b [mm] d [mm] h [mm] Type of fiber [-] n l

[-] t eq

[mm] f mc

[MPa] f m0

[MPa] f mc

/f mc0 1.519 2.016 1.679

[-]

S24 S25 S26

54 54 54

54 54 54

85 85 85

Carbon Carbon Carbon

0.125 0.0206

20.63 27.38 22.80

13.58 13.58 13.58

0.25

0.0413

0.167 0.0275

Table 5.B : Geometrical characteristics and experimental results [35].

k eff [-]

f l,(eq.13) [MPa]

f l,eff,(eq.13) [MPa]

(f l,eff

/ f m0

), (eq.13)

f l, (eq.18) [MPa]

f l,eff, (eq.18) [MPa]

(f l,eff

/ f m0

), (eq.18)

ID specimen

[MPa] 0.0292 0.0583 0.0389

[MPa] 0.0292 0.0583

S24 S25 S26

0.15 0.15 0.15

2.62 5.24 3.49

0.40 0.79 0.53

2.62 5.24 3.49

0.40 0.79 0.53

0.0389 Table 6.B : Effective confining stress calculated according to Eqns. (13) and (18) for the experimental program [35].

ID specimen b [mm] d [mm] h [mm] Type of fiber [-] n l

[-] t eq

[mm] f mc

[MPa] f m0

[MPa] f mc

/f mc0 2.526 2.818 2.293 2.496 1.440 1.600 1.798 1.803

[-]

S27 S28 S29 S30 S31 S32 S33 S34

240 240 240 240 240 240 240 240

240 240 240 240 240 240 240 240

500 500 500 500 500 500 500 500

Carbon Carbon

1 2 2 3 1 2 2 3

0.131 0.262

13.374 14.922 12.142 13.215

5.295 5.295 5.295 5.295 3.299 3.299 3.299 3.299

Glass Glass

0.34 0.51

Carbon Carbon

0.131 0.262

4.751 5.279 5.930 5.948

Glass Glass

0.34 0.51

Table 7.B : Geometrical characteristics and experimental results [36].

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