Aggregates

Compressive strength

7 days

21 days

28 days

Natural sand

Average

12.37

14.79

16.51

IC (95%)

[5.46 - 19.27]

[8.83 - 20.76]

[9.76 - 23.25]

Standard deviation

7.05

6.08

6.88

Improved sand

Average

22.88

23.79

28.32

IC (95%)

[21.21 - 24.55]

[22.63 - 24.96]

[27.4 - 29.25]

Standard deviation

1.48

1.03

0.82