Issue 67

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

Pre-stressing System

Py

∆y

µ

model

No. of strands

kN

mm

S2

6

287.155

6.582

1.47

S5

6

236.2

7.47

1.58

S7

6

231.2

7.9

2.05

S8

6

214.1

8.2

2.13

Table 5: Ductility for solid specimens (control/S2) and other specimens with openings of flat slab subjected to 6 strands.

Ultimate Point

Yielding Point

Load (kN)

Deflection (mm)

Figure 22: Indication for deducing Yielding point and Ultimate point from Load mid-span deflection curve.

2,50

2,50

2,18

2,13

2,10

2,05

2,00

2,00

1,62

1,58

1,54

1,47

S1 s3 S4 S6

S2 S5 S7 S8

1,50

1,50

1,00 Ductility

1,00 Ductility

0,50

0,50

0,00

0,00

Figure 23: Ductility induced from 4 strands post-tensioned flat slab.

Figure 24: Ductility induced from 6 strands post-tensioned flat slab.

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