Fatigue Crack Paths 2003

superplasticizer was increased up to 10 litres/m3 when the fibres were added to the

mixture.

A

150 m m

m m

m m

1 5 0

1 5 0

a

= 45 m m

0

A

Sect.

’

450 m m

A-A’

600 m m

(a)

(b)

Figure 2. Specimen geometry for bending static tests (a) and tensile cyclic tests (b).

In Table 1 the geometrical and mechanical characteristics of the four types of steel

fibres used in this research are reported. The fibres are conventionally classified as

macro, meso or micro according to their diameter.

Table 1. Geometrical and mechanical properties of the steel fibres.

Shape

Type of steel fibre

Length lf [mm] Diameter If [mm]

raAtsiopecLt/I

Tensile str gth ft

[MPa]

Macro

30

0.60

50

1200

Hooked

Straight

Meso1

20

50

1100

0.40

Straight

Meso2

10

0.40

25

1100

Straight

Micro

66.6

1800

12

0.18