Factors Affecting The Values - Proceq N Mode D'emploi

60
50
40
30
20
10
20 25 30 35
Rebound Value R
Fig. 2.9 J-Curve "Early Strength"
60
50
40
30
20
10
20 25 30 35
Rebound Value R
Fig 2.10 J-Curve "Blast Furnace"
© 2017 Proceq SA
B-Proceq
Early Strength
40 45 50
B-Proceq
Blast Furnace
40 45 50
2 .5

Factors Affecting the Values

2 .5 .1 Direction of Impact
The measured rebound value R is dependent on the
impact direction.
2 .5 .2 Shape coeficient
The compressive strength measured in a pressure testing
machine depends on the shape and size of the sample.
The samples prescribed for use in the
particular country must be taken into account
when converting the rebound value R into
compressive strength.
In the conversion curves on page 7 to page 11, the
values for compressive strength are specified for cylin-
ders (Ø 150 x 300 or Ø 6" x 12") and for cubes (length of
side 15 cm). The following shape coefficients are familiar
from the literature:
Cube 150 mm
Shape 1 .00
coeficient 1.25
Cylinder Ø 150x300 mm
Ø 6"x12"
Shape 0.80
1.00
coeficient
Drill core Ø 50x56 mm
Shape 1.04
coeficient 1.30
Measurement
200 mm 300 mm
0.95 0.85
1.19 1.06
Ø 100x200 mm Ø 200x200 mm
0.85 0.95
1.06 1.19
Ø 100x100 mm Ø 150x150 mm
1.02 1.00
1.28 1.25
11