MEASURING RHEOLOGICAL MEASURING RHEOLOGICAL MEASURING RHEOLOGICAL

PROPERTIES OF FRESH PROPERTIES OF FRESH PROPERTIES OF FRESH

MORTARS WITH CONCRETE MORTARS WITH CONCRETE MORTARS WITH CONCRETE

RHEOMETERSRHEOMETERSRHEOMETERSAndraž Hočevar, Franci Kavčič, Igmat d.d.

Violeta Bokan Bosiljkov, UL FGG

University of LjubljanaFaculty of Civil and Geodetic Engineering

"Rheology of Building Materials", Regensburg, March, 12-13, 2014 2 | 20

OUTLINEOUTLINEOUTLINE

Motive

Rheometers

Test program

Results

Conclusions

"Rheology of Building Materials", Regensburg, March, 12-13, 2014 3 | 20

MOTIVEMOTIVEMOTIVE

Design process of concrete mixture can be time and

raw materials consuming

Concrete rheometers demand high volume of fresh

concrete

Tests on corresponding mortar

Concrete equivalent mortar (CEM) method

"Rheology of Building Materials", Regensburg, March, 12-13, 2014 4 | 20

MOTIVEMOTIVEMOTIVE

Aim of this presentation is to show pluses and

minuses of smaller measuring systems

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RHEOMETERSRHEOMETERSRHEOMETERS

ConTec Viscometer 5

Outer cylinder radius, Ro = 100 mm

Inner cylinder radius, Ri = 85 mm

Height of the cylinder is measured, (h ≈ 85 mm)

"Rheology of Building Materials", Regensburg, March, 12-13, 2014 6 | 20

RHEOMETERSRHEOMETERSRHEOMETERS

ConTec Viscometer 5

Outer cylinder radius, Ro = 100 mm

Inner cylinder radius, Ri = 85 mm

Height of the cylinder is measured, (h ≈ 85 mm)

"Rheology of Building Materials", Regensburg, March, 12-13, 2014 7 | 20

RHEOMETERSRHEOMETERSRHEOMETERS

ICAR Rheometer

Outer cylinder radius, Ro = 74 mm

Inner cylinder radius, Ri = 64 mm

Height of the cylinder, h = 127 mm

"Rheology of Building Materials", Regensburg, March, 12-13, 2014 8 | 20

RHEOMETERSRHEOMETERSRHEOMETERS

ICAR Rheometer

Outer cylinder radius, Ro = 74 mm

Inner cylinder radius, Ri = 64 mm

Height of the cylinder, h = 127 mm

"Rheology of Building Materials", Regensburg, March, 12-13, 2014 9 | 20

TEST PROGRAMTEST PROGRAMTEST PROGRAM

26 mortars from ordinary concrete and 12 mortars from SCC

mixtures

Rheology and slump flow with equipment for flow table spread

of mortar (SIST EN 1015-3:2001)

Mixing procedure (5 min):

Dry constituents - 1 min

Half of the water, 0.3 l of water with diluted liquid

admixtures, rest of the water - 1 min (while mixing)

Mixing for another - 3 min

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TEST PROGRAMTEST PROGRAMTEST PROGRAM

Measuring procedure:

Enlarged version of standard mortar mixer

Each mixture mixed once

Average of 3 repetitions

Remixed with flat rod before each measurement

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TEST PROGRAM TEST PROGRAM TEST PROGRAM --- mixturesmixturesmixtures

------3,1922,1281,064GGBS (kg)

---102406203---Silica fume (g)

224896448------Tuff (g)

27,7226,8827,4416,6816,3416,5710,8610,9811,09Superplastizicer (g)

2,9322,9322,9322,9322,9322,9322,9322,9322,932Water (kg)

13,03213,03213,03213,03213,03213,03213,03213,03213,032Aggregate – 0/2 (kg)

5,324,485,045,465,045,322,243,364,48CEM I 42,5 R (kg)

MT1CMT1BMT1AMM1CMM1BMM1AMZ1CMZ1BMZ1A

---11,208,405,60---Stabilizer (g)

------2,803,362,24Air entrainer (g)

------5,605,605,60Superplasticizer (g)

3,4283,2623,0983,5883,5883,5882,9322,9322,932Water (kg)

13,03213,03213,03213,03213,03213,03213,03213,03213,032Aggregate – 0/2 (kg)

------5,605,605,60CEM II/A-M (LL-S) 42,5 R (kg)

5,605,605,605,605,605,60---CEM I 42,5 R (kg)

MV1CMV1BMV1AMG1CMG1BMG1AMRA1CMRA1BMRA1A

16,811,25,6-16,811,25,6-Superplasticizer (g)

2,9322,9322,9322,9322,9322,9322,9322,932Water (kg)

13,03213,03213,03213,03213,03213,03213,03213,032Aggregate – 0/2 (kg)

----5,605,605,605,60CEM II/A-M (LL-S) 42,5 R (kg)

5,605,605,605,60----CEM I 42,5 R (kg)

ML1CML1BML1AML1MR1CMR1BMR1AMR1

MORTARS FROM ORDINARY CONCRETE

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TEST PROGRAM TEST PROGRAM TEST PROGRAM --- mixturesmixturesmixtures

99,2699,2699,2699,2699,26Superplasticizer – polyphosponic (g)

3,0323,0323,0323,0323,032Limestone filler (kg)

13,40513,40513,40513,40513,405Aggregate – 0/2 (kg)

3,0522,7722,8422,9282,912Water (kg)

5,605,605,605,605,60CEM I 42,5 R (kg)

MR4DMR4CMR4BMR4AMR4

19,6016,8014,0011,205,60--Stabilizer - powder (g)

39,2045,7250,6255,5260,4260,4260,42Superplasticizer (g)

-0,9321,6312,3323,0323,0323,032Limestone filler (kg)

14,83614,23213,77813,32612,88613,47014,052Aggregate - 0/2 (kg)

3,2483,2483,2483,2483,2482,9122,576Water (kg)

5,605,605,605,605,605,605,60CEM I 42,5 R (kg)

MM4MM3MM2MM1MR3MR2MR1

MORTARS FROM SCC

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TEST PROGRAMTEST PROGRAMTEST PROGRAM

Calculation of fundamental results Shear thickening behavior observed Bingham model on bottom 4 points

−

=

i

o

oi

R

Rh

RRT

ln4

1122

0

π

τ

SRRhoi

111

8

1222

−=

πµ

T = intersectionS = slope

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RESULTS RESULTS RESULTS ––– mixmixmix bybyby mixmixmix

Yield values – ordinary mortars

Lines are parallel Bigger difference between rheometers at higher values

Repeatability is better for ConTec

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RESULTS RESULTS RESULTS ––– mixmixmix bybyby mixmixmix

Plastic viscosity – ordinary mortars Lines are parallel, values almost identical

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RESULTS RESULTS RESULTS ––– mixmixmix bybyby mixmixmix

Yield value – SCC mortars

ICAR has zero values!

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RESULTS RESULTS RESULTS ––– mixmixmix bybyby mixmixmix

Plastic viscosity – SCC mortars

Lines are parallel, values almost identical

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RESULTS RESULTS RESULTS ––– correlationcorrelationcorrelation ofofof

rheometersrheometersrheometers

Ordinary mortar

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RESULTS RESULTS RESULTS ––– correlationcorrelationcorrelation ofofof

rheometersrheometersrheometers

SCC mortarAs expected correlation for yield values is not OK

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AdditionalAdditionalAdditional analysisanalysisanalysis

Analysis of variance: Change of mix design is statistically significant

with 5% risk for both rheological parameters Except for ICAR rheometer measuring yield

values of SCC mortar

Post hoc tests (Duncan, Bonferroni) tell us that ICAR has bigger variances inside measurements

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ZERO VALUES ZERO VALUES ZERO VALUES ––– WHY?WHY?WHY?

Is ICAR sensitive enough for measuring mortar?

Shear rate?

[1]

Small container gives us bigger shear rate!

Big vane in small container! Secondary flows?

[1] Feys, D., Verhoeven, R., De Schutter, G. 2007. Evaluation of time independent rheological models applicable to fresh self-compacting concrete. Applied Rheology 17, 5, 56244: 1-10.

Ω−

+=

22

22

io

io

RR

RRγ&

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CONCLUSIONSCONCLUSIONSCONCLUSIONS

In analysis we observe similar trends for both rheometers, except for yield values of SCC mortars.

ICAR Rheometer is not suitable for measuring too liquid mortars.

Further development is needed – container and vane size should be decreased proportionally, change theshape of vane.

Measurements should be done with appropriate shear rates.

THANK YOU FOR YOUR THANK YOU FOR YOUR THANK YOU FOR YOUR

ATTENTION!ATTENTION!ATTENTION!

University of LjubljanaFaculty of Civil and Geodetic Engineering