Issue 59

T. Djedid et alii, Frattura ed Integrità Strutturale, 59 (2022) 580-591; DOI: 10.3221/IGF-ESIS.59.38

The particle size distribution of each aggregate is shown in Fig. 2.

Chemical composition (% wt)

CaO Al 2 O 3 SiO 2 Fe 2 O 3 61.90 4.15 15.80 2.31

Na 2 O SO 3 K 2 O Cl -

MgO IR

Loss on ignition

Free CaO

0.06 2.80 0.69 0.02 3 2.39 0.7-2

9.59

1

Mineralogical composition (%)

C 3 S

C 2 S

C 3 A

C 4 AF

58

16

7

12

Physical and mechanical properties

Specific gravity (g/cm 3 )

3.22

Blaine specific surface area (cm 2 /g)

3750 – 5250

Initial set (min) Final set (min)

150 188

Consistency of cement paste (%)

28

Strength class (MPa)

42.5

Table 1: Physico-chemical, mineralogical and mechanical characteristics of cement.

Sand

Gravel

CG

Type

RS

CS

3/8

8/16 1.381 2.654

Apparent volumetric mass (g/cm 3 ) Absolute volumetric mass (g/m 3 )

1.638 2.628

1.506

1.308 2.620

2.55

Fineness modulus Sand equivalent (%)

2.33

1.735 80.87

- -

- -

80.69

Aggregate cleanness (%)

-

-

98.98

99.13

Water absorption after 24 h (%)

2.13

4.1

2.5

1.21

Flatness coefficient (%) Los Angeles testing (%)

- -

- -

30

17.13 26.52

27.60

Insoluble (%)

99

38

- - -

- - -

SO 4 -2 content (%) CaCO 3 content (%)

0.69

0.62

0

58.07

Table 2: Physico-chemical characteristics of studied aggregates.

a) River sand.

b) Crushed limestone sand.

c) Silica-limestone fines.

Figure 1: Photos illustrate the sands and fines studied.

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