Sliding Pipe Rheometer (Sliper)

Faculty of Civil Engineering Institute of Construction Materials

1st International RILEM Conference on Rheology and Processing of Construction Materials, Paris, 2 – 4 September, 2013

Experimental Study on Pumpability of Concrete using Sliding Pipe Rheometer Nerella Venkatesh Naidu M.Sc Institute of Construction Materials, TU Dresden Dr. Knut Kasten Putzmeister Engineering GmbH Prof. Dr. Viktor Mechtcherine Institute of Construction Materials, TU Dresden

Introduction Testing concrete pumpability

Pumpability

• Why? − To develop concrete compositions for reliable pumping − Discharge pressure estimation  Selection of machines

Circuit

Aggregate grading, Shape

• Methods − Traditional methods have limitations − New, reliable and portable devices are needed

Admixtures

Super-plasticizer, Stabilizer…

Water-to-binder ratio

(Putzmeister) TU Dresden, Institute of Construction Materials, V. N. Nerella, K. Kasten, V. Mechtcherine

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Sliding Pipe Rheometer (Sliper) New approach for testing pumpability

Pipe

Weights

Pressure sensor

Pressure (P) B

Piston Displacementsensor Sliding Pipe Rheometer (Kasten et al.2010, Nerella 2012)

A Flow Rate (Q) d) Pumpability curve (A and B are related to yield stress and plastic viscosity, respectively)

TU Dresden, Institute of Construction Materials, V. N. Nerella, K. Kasten, V. Mechtcherine

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Experimental program Testing equipment and investigated parameters Flow table test

Sliper test

Viscometer test

(DIN EN 12350-5, 1999)

Investigated parameters • • • • • •

Water-to-binder ratio Aggregate shape Addition of silica fume Addition of fly ash Consistency Cement type


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Concrete composition schema

Parameter

Mix

Cement

CEM II

Concrete

CEM I

Ordinary

HPC

Aggregate shape

Rounded

W/B

0.45

0.6

Consistency

F3

F3

F3

F5

F3

Mineral admixture

-

-

-

-

-

Number

1

Crushed

2

0.45

3

4

Ordinary

Rounded

Crushed

Rounded

0.3

0.3

0.45

5

F3

-

6

Silica fume

7

F5

Fly ash

8


-

9

Silica fume

10

F3

Fly ash

11

-

12

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Results Relation between concrete composition and pumpability 35

11

30

6

5 Pressure P (kPa)

25 20

8

7

10 w/b = 0.30

4 3

12

15

1

10

2

w/b = 0.45 5

w/b = 0.60 0 0

10

20

30

40 50 Flow rate Q (m3/h)

60

70

80

Parameter

Mixtures to compare

Aggregate shape W/B Silica Fume (SF) Fly Ash (FA) Cement type

1 (round) with 3 (crushed) | 5 (round) with 6 (crushed) 2 (0.6) with 3 or 6 (0.3) | 1 (0.45) with 5 (0.3) 6 (without SF) with 7 (with SF) 6 (without FA) with 8 (with FA) 1 (CEM II) with 12 (CEM I)

Consistency

3 (F3) with 4 (F5) | 7 (F3) with 10 (F5) | 8 (F3) with 11 (F5)


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Pumpability – Effect of water-to-binder ratio 35 30

Crushed aggregates Consistency F3 CEM II no SF, no FA

w/b = 0.30

Pressure P (kPa)

25

6 20 w/b = 0.45 15

3 10

w/b = 0.60 5

2 0 0

10

20

30 40 50 Flow rate Q (m3/h)

60

70

80

 Predominant influence – higher the w/b lower the pumping pressure


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Pumpability – Effect of water-to-binder ratio 35

11 6

30

8

5

Pressure P (kPa)

25

w/b = 0.30

7

20

10

15

3

w/b = 0.45

4

12

1

10

2 w/b = 0.60

5 0 0

10

20

30 40 50 Flow rate Q (m3/h)

60

70

80

 Predominant influence – higher the w/b lower the pumping pressure  Grouping on P-Q Curve


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Pumpability – Effect of aggregate shape 35

Consistency F3 CEM II no SF, no FA

6 30

5

Pressure P (kPa)

25 20

w/b = 0.30

1

3

15 10 w/b = 0.45

5 0 0

10

20

30 40 Flow rate Q (m3/h)

50

60

70

 Round aggregate mixtures have higher pumpability

• Crushed aggregates − High surface area (more paste required) − Friction and interlocking TU Dresden, Institute of Construction Materials, V. N. Nerella, K. Kasten, V. Mechtcherine

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Pumpability – Effect of mineral admixtures 35

Crushed aggregates Consistency F3 W/B = 0.30 CEM II

Pressure P (kPa)

30 25

Ref

Ref + FA

20

Ref + SF

15 10 5 0

0

5

10

15

20

25

30

35

Flow rate Q (m3/h)

 SF increased pumpability while FA decreased it (when added “on top”!)  Many variables  No general conclusions Cement Silica fume Fly ash Water W/B

6 - Ref 450

135 0.3

7 - SF 450 45

148.5 0.3

8 - FA 450

• Silica fume

100 147

• Fly ash (here counted with 40%)

− Reduced plastic viscosity

− Increased plastic viscosity

0.3


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Pumpability – Effect of consistency 35

11 (FA)

Consistency F3 Consistency F5 Crushed aggregates CEM II

30

8 (FA)

Pressure P (kPa)

25

7 (SF) 10 (SF)

20 w/b = 0.30

3

15

4

10

(BASF, 2008)

w/b = 0.45

5 0

0

10

20

30

40 50 3 Flow rate Q (m /h)

60

70

80

• Higher SP  lower plastic viscosity  higher pumpability TU Dresden, Institute of Construction Materials, V. N. Nerella, K. Kasten, V. Mechtcherine

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Comparison – Plastic viscosity


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Comparison – Yield stress


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Validation Field measurements (full scale pumping) vs. Sliper estimations OC Field

14

OC Sliper

12 Pressure P (Mpa)

SCC Field 10

SCC Sliper

8 6 4 2 0 0

10 20 30 40 50 60 70 80 90 100 Flow rate Q (m3/h)


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Summary • Sliper is a new, portable device to test pumpability of concrete • Sliper clearly demonstrated the influence of concrete composition on pumpability • Sliper results correlated well with viscometer results

• Pressure predictions using Sliper approach were validated with field measurements successfully


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Outlook Time/Pumpability

Sliper wall – DEM

A cross-platform study on influence of time on concrete pumpability

Temperature/Pumpability A cross-platform study on influence of temperature on concrete pumpability

Numerical Model Computation Fluid Dynamics Method • Single fluid approach • Flow patterns of concrete flow in pipes

Viscosity contours – CFD

Distinct Element Method • Particle-flow approach • Micro-mechanical model • SIPM, lubricating layer … TU Dresden, Institute of Construction Materials, V. N. Nerella, K. Kasten, V. Mechtcherine

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Literature Mix-Compositions, experimental results and detailed analyses in

1.

V. N. Nerella “Experimental and Numerical Study on Pumpability of Concrete using Sliding Pipe Rheometer and ANSYS Fluent”, Master Thesis supervised by Uni. Prof. Dr.-Ing. V. Mechtcherine, Institute of Construction Materials, TU Dresden, 26. Sep. 2012.

2.

V. Mechtcherine, V. N. Nerella, and K. Kasten “Testing pumpability of concrete using Sliding Pipe Rheometer,” Construction and Building Materials, vol. 53, pp. 312–323, Feb. 2014.


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Literature [1]

S. Jacobsen, J. H. Mork, S. F. Lee, and L. Haugan, “Pumping of concrete and mortar – State of the art,” 2008.

[2]

K. Kasten, “Gleitrohr – Rheometer, Ein Verfahren zur Bestimmung der Fließeigenschaften von Dickstoffen in Rohrleitungen [in German],” TU Dresden, 2010.

[3]

D. J. Seon, C. K. Park, J. H. Jeong, S. H. Lee, and S. H. Kwon, “A Computational Approach to Estimating a Lubricating Layer in Concrete Pumping,” vol. 27, no. 3, pp. 189–210, 2012.

[4]

“Testing fresh concrete- Part 5- Flow table test. DIN EN 12350-5; Prüfung von Frischbeton – Teil 5: Ausbreitmaß. Deutsche Fassung DIN EN 12350-5,” 1999.

[5]

T. C. Holland, “FHWA-IF-06-0106: Silica Fume User’s Manual,” 2005.

[6]

C. P. G. BASF, “Mode of Action of Superplasticizers for cement based construction materials - Technical Leaflet,” in in Construction Polymers, 2008, pp. 1–2.


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THANK YOU

V. N. Nerella TU Dresden

Prof. Dr.-Ing. V. Mechtcherine, TU Dresden


Dr.-Ing. K. Kasten, Putzmeister Engineering GmbH

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