Corrections - Proceq DIGI-SCHMIDT 2000 ND Operating Instructions Manual

4.4.2 Select Curve
The compressive strength of the concrete fck can be cal-
culated from the rebound value R by means of conver-
sion curves. There are 3 options available for calculating
the compressive strength of the concrete:
- No conversion
- Select 5 internal conversion curves, or
- Choose between 2 programmed PROCEQ standard
curves (fck 7 days and fck 14 to 56 days).
No Conversion
Select "No Conversion".
At the end of a measurement series, only the average of
the rebound values in relation to the impact direction is
displayed.
The corresponding compressive strengths of the con-
crete can be taken from the conversion curves in Fig. 8.1
and Fig. 8.2 under "Standard Conversion Curves",
page 19 and page 20.
Internal Conversion Curves
Parameters a, b and c of the curve functions must first
be set in the sub-menu "Set up curve".
• Under line number 1 to 5, select the conversion curve.
Select PROCEQ Standard Curves
For the derivation of the PROCEQ Standard curves, refer
to "Derivation of the PROCEQ Standard Conversion
Curves", page 19.
© 2001 PROCEQ SA
• Select conversion curve A in line no. 7 for concrete
with an age of 7 days (fck7) or the conversion curve in
line no. 28 for concrete with an age of 14 - 56 days
(fck28).
4.4.3 Set up Curve
The curve no. (1 to 5) and the parameters a, b and c
(see under "Creating New Conversion Curve", page 20)
can be set using the arrow keys.
4.5

Corrections

Shape Coefficient αs
4.5.1
The PROCEQ standard curves fck7 and fck28 are valid
for sample cubes with a 200 mm side for EPROM
versions up to 1.3 or from a 150 mm side from EPROM
version 2.0. If test specimens with different dimensions
are used for determining the compressive strength in the
pressure testing machine, the shape coefficient in the
first line is to be set or selected in line 2 to 4.
Shape of the test specimen:
1. Line: "variable", see Table 4.1
Test specimen
Cube 300 mm and cylinder Ø 100x100 mm
Drill core Ø 100x100 mm
Drill core Ø 50x56 mm
Tab. 4.1 Shape coefficients
Settings
Shape coeffi-
cients
EPROM version up to 1.3 from 2.0
0,90
1,07
1,09
0,85
1,02
1,04
7