Issue 67

A.Zamrawi et alii, Frattura ed Integrità Strutturale, 67 (2024) 292-310; DOI: 10.3221/IGF-ESIS.67.21

Pre-stressing System No. of strands

Pmax

∆max

Model

kN

mm

S2 S5 S7 S8

6 6 6 6

345.932 286.485 284.421 265.933

9.7

11.8 16.2

17.496

Table 3 : Failure load and mid-span deflection comparisons between solid specimens (S2), and other specimens with openings subjected to 6 strands.

100 150 200 250 300 350

100 150 200 250 300 350

Load (kN)

Load (kN)

0 50

0 50

0

5

10 15 20 25

0

5

10

15

20

25

Deflection (mm)

Deflection (mm)

s1

s3

s4

s6

s2

s5

s7

s8

Figure 12: Load versus mid-span deflection for flat slab subjected to 4 strands, for control specimen (S1) and specimens with openings.

Figure 13: Load versus mid-span deflection for flat slab subjected to 6 strands, for control Specimen and specimens with openings.

100 150 200 250 300 350 400 Pmax (kN)

100 150 200 250 300 350 400

345,9315

286,4854278

300,81

284,420668

265,9333245

245,190231 258,09498

230,4788171

Pmax (kN)

0 50

0 50

1

S1 S3 S4 S6

S2 S5 S7 S8

Figure 14: Load comparisons between control Specimen(S1) and specimens with openings subjected to 4 strands

Figure 15: Load comparisons between control specimen(S2) and specimens with openings subjected to 6 strands.

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