Issue56

K.C. Nehar et alii, Frattura ed Integrità Strutturale, 56 (2021) 203-216; DOI: 10.3221/IGF-ESIS.56.17

40

30

20

10

Compressive strength at 28 days (MPa)

0

RC (100%)

NC (100%)

(70%NA+30%RA)

(50%NA+50%RA)

Figure 1: The compressive strength at 28 days of reference concrete.

A (kg/m 3 )

C (kg/m 3 ) 450.70 522.46 472.13 484.60

SF (%)

Adj. (%) W/B

Sagging (cm)

Fresh density

Types of concrete

8/15 3/8 0/5

NC+SF RC+SF

950 200 670 60.2 10.5 0.30 950 200 670 70.4 14.2 0.37 950 200 670 65.6 11.7 0.32 950 200 670 72.3 13.4 0.35

5.0 5.7

2567 2389 2465 2332

(70%NA+30%RA+SF) (50%NA+50%RA+SF)

4 3

Table 5: Composition of concrete mixes.

90

80

70

60

50

40

30

20

10

Compressive strength at 28 days (MPa)

0

RC+SF

NC+SF

(50%NA+50%RA+SF)

(70%NA+30%RA+SF)

Figure 2: The compressive strength at 28 days of concrete mixes.

Fig. 2 shows the compressive strength at 28 days obtained with this optimal formulation.

208