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Development of a Fiber Reinforced Self-Compacting Heavyweight Concrete by
Considering the Factory Conditions
Entwicklung eines faserbewehrten selbstverdichtenden Schwerbetons unter Berücksichtigung der Werksbedingungen
M. Sc. Klemens Laub
Dipl.-Ing. (FH) Markus Tenwinkel Dr.-Ing. Barbara Leydolph
Dr.-Ing. Ulrich Palzer
25. Conference: "Rheology of Building Materials", Regensburg 02.03.2016
Cooperation Project Kooperationsprojekt
25. Conference: "Rheology of Building Materials", Regensburg 1
Zentrales Innovationsprogramm Mittelstand – ZIM
Objective Target of the Project Zielstellung des Projektes
“Development of a low-shrinkage, deformation-resistant, high-performance material with optimized dynamic load capacity for high-stressed ballast components of vehicles in aggressive environments” „Entwicklung eines schwindarmen, verformungsstabilen Hochleistungswerkstoffs mit optimierter dynamischer Belastbarkeit für hochbeanspruchte Ballastierungskomponenten im Fahrzeugbau in aggressiver Umgebung“
25. Conference: "Rheology of Building Materials", Regensburg 2
Main Approach
Deformation-resistance and dynamic load capacity
Fibers
Low dynamic E-Modulus
High tensile strength
Aggressive environment
Coating
Frame conditions:
− Density: ≥ 4000 kg/m³
− Acceptable early strength
Homogenous structure, no blowholes
25. Conference: "Rheology of Building Materials", Regensburg 3
Factory Conditions
25. Conference: "Rheology of Building Materials", Regensburg 4
bench-scale
Factory Conditions
Available and no change
1) Cement
2) Water
3) Fly ash
4) Fine aggregate
5) Coarse aggregate
6) Superplasticizer
Additional
7) Powder
8) Admixture
9) Fibers
25. Conference: "Rheology of Building Materials", Regensburg 5
SCC Concept
Why SCC?
High surface quality − Less rework (bubbles/blowholes)
Complete filling of: − Complex formworks
− Reinforced formworks
Fibers are more effective: − Better activation in mortar matrix
− Orientation in flow direction
No vibration: − Less noise pollution
− Less man power needed
− Less physiological stress
25. Conference: "Rheology of Building Materials", Regensburg 6
SCC Concept
25. Conference: "Rheology of Building Materials", Regensburg 7
SCC typical vol.-%
Components factory
Density kg/m³
Composition
10.3 Cement 3005 Paste
ρ ≈ 1800
kg/m³
Mortar
ρ ≈ 3140 kg/m³
10.4 Fly ash 2400
18.4 Water + SP 1000
2.4 Air void 0
28.8 Fine aggregate
0/2 5100 Aggregate
ρ ≈ 5050
kg/m³ 28.9 Coarse
aggregate 4/16
5000 Aggregate ρ ≈ 5000
kg/m³
Δρ ≈ 1860 kg/m³
Challenge:
Difference in density
Segregation
Solution:
Increasing paste density
Procedures:
Okamura et al. [1]
DAfStb-Guideline [2] Iron oxide d50 ≈ 35µm ρ ≈ 5400 kg/m³
SCC Concept
Paste
• Saturation point (βP)
• Robustness (slope)
• Calculated density
Mortar
• Slump
• V-funnel for mortar
• Density
Concrete
• Slump-flow
• V-funnel for SCC
• Density
25. Conference: "Rheology of Building Materials", Regensburg 8
Design of Experiments
• Pretesting
• Mixture-Design
• 3 components
• 18 runs
Design of Experiments
• Pretesting
• Central-Composite-Design
• 3 factors
• 17 runs
Variation
• w/c
• Cement content
• Fibers
• Mixing process
Procedure
Components
• Cement [vol.-%]
• Fly Ash [vol.-%]
• Powder [vol.-%]
Factors
• βP correction k [-]
• Fine aggregate [vol.-%]
• Superplasticizer [sp/c %]
Mix Design – Paste
Methods − VW/VP at saturation point (βP)
− Slope as measure for robustness
− Calculated density with water at βP
Experimental design based on pretesting − FA improves robustness,
packing density, workability
− Disadvantage: FA reduces density
25. Conference: "Rheology of Building Materials", Regensburg 9
ΔH2O
ΔSFM (red)
ΔSFM (green)
260
280
300
320
340
360
380
150 170 190 210 230 250
Wat
er
[g]
Slump [mm]
βP
0,8
0,9
1,0
1,1
1,2
1,3
0 1 2 3 4 5
Vw
/VP [
-]
Rel. spread Γ [-]
Mix Design – Paste
Results
25. Conference: "Rheology of Building Materials", Regensburg 10
Solution βP [-] Slope [-] Calc. density [kg/m³]
with fly ash 0.933 0.077 2573
without fly ash 0.953 0.051 2733
Numeric optimization
Design-Expert® SoftwareComponent Coding: ActualDensity at ß [kg/m³]
Design Points2781
2442
X1 = A: Cement [vol.-%]X2 = B: Iron oxide [vol.-%]X3 = C: FA [vol.-%]
A: Cement [vol.-%]60
B: Iron oxide [vol.-%]
60
C: FA [vol.-%]
20
0 40
40
Density at ß [kg/m³]
2500
2600
2700
Design-Expert® SoftwareComponent Coding: ActualOriginal Scale (median estimates)Slope [-]
Design Points0.092
0.044
X1 = A: Cement [vol.-%]X2 = B: Iron oxide [vol.-%]X3 = C: FA [vol.-%]
A: Cement [vol.-%]60
B: Iron oxide [vol.-%]
60
C: FA [vol.-%]
20
0 40
40
Slope [-]
0.050
0.050
0.060
0.070
0.080
Design-Expert® SoftwareComponent Coding: Actualß [-]
Design Points1.068
0.821
X1 = A: Cement [vol.-%]X2 = B: Iron oxide [vol.-%]X3 = C: FA [vol.-%]
A: Cement [vol.-%]60
B: Iron oxide [vol.-%]
60
C: FA [vol.-%]
20
0 40
40
ß [-]
0.900
0.920
0.940
0.960
0.980
1.000
190
195
200
205
210
215
220
225
230
0 100 200 300 400 500 600
Slu
mp
[m
m]
Time [s]
Mix Design – Mortar
Pretesting
− Constant amount stabilizer Extended mixing time
− Efficiency SP and thixotropy
− Time-dependent slump 4 points Function
Which yield point or slump is required for sedimentation- stable SCC?
25. Conference: "Rheology of Building Materials", Regensburg 11
Mix Design – Mortar
Estimated max. slump
of the SCC mortar
25. Conference: "Rheology of Building Materials", Regensburg 12
𝜏0 ≥ 𝐾 𝜌𝐺 − 𝜌𝐹𝑙 𝑑𝐺𝑔
Roussel et al. [8]
𝜏0 =225𝜌𝐹𝑙𝑔𝛺2
128𝜋2𝑅5
𝑅 = 0.708 𝜌𝐹𝑙𝑔𝛺2
𝜏0
5
Stability criterion Geometry K
Theoretical sphere 1
18
Jossic et al. [3] sphere (rough)
1
17.2
Ansley et al. [4] sphere 4
21𝜋
Bethmont et al. [5] sphere 1
18.4
Beris et al. [6] sphere 1
21
Vogel [7] sphere
2
3𝜋
aggregate ~0.3
Unit Ordinary Heavy
𝝆𝑮 kg/m³ 2600 – 2750 5000
𝝆𝑭𝒍 kg/m³ 2000 – 2400 3200 - 3900
𝝆𝑮 − 𝝆𝑭𝒍 kg/m³ 200 – 650 1100 - 1800
𝒅𝑮 mm 16 16
Mix Design – Mortar
25. Conference: "Rheology of Building Materials", Regensburg 13
SCC mortar heavy SCC mortar 100
120
140
160
180
200
220
240
260
280
300
320
340
1400 1600 1800 2000 2200 2400 2600 2800 3000 3200 3400 3600 3800 4000 4200 4400 4600
Max
. slu
mp
wit
h d
G =
16
mm
[m
m]
Fresh mortar density ρFl [kg/m³]
Beris
Bethmont
theoretical
Jossic and Magnin
Ansley and Smith
Vogel (sphere)
Vogel (aggregate)
ρG = 2600 kg/m³
ρG = 5000 kg/m³
Mix Design – Mortar
Results
25. Conference: "Rheology of Building Materials", Regensburg 14
Numeric optimization
Solution Slump [mm] V-funnel [s] Density [kg/m³]
with fly ash 295 6.3 3571
Design-Expert® SoftwareFactor Coding: ActualFresh mortar density [kg/m³]
Design Points3703
3452
X1 = A: Sand [vol.-%]X2 = C: k [-]
Actual FactorB: Superplastisizer [sp/c %] = 3.875
35 38 40 43 45
0.80
0.83
0.85
0.88
0.90Fresh mortar density [kg/m³]
A: Sand [vol.-%]
k [-]
3500 3550 3600 36503
Design-Expert® SoftwareFactor Coding: ActualSlump [mm]
Design Points326
273
X1 = A: Sand [vol.-%]X2 = C: k [-]
Actual FactorB: Superplastisizer [sp/c %] = 3.875
35 38 40 43 45
0.80
0.83
0.85
0.88
0.90Slump [mm]
A: Sand [vol.-%]
k [-]
280
290300
310
3
Design-Expert® SoftwareFactor Coding: ActualOriginal Scale (median estimates)V-funnel [s]
Design points above predicted valueDesign points below predicted value10.8
3.6
X1 = A: Sand [vol.-%]X2 = C: k [-]
Actual FactorB: Superplastisizer [sp/c %] = 3.875
0.80
0.83
0.85
0.88
0.90
35
38
40
43
454.0
6.0
8.0
10.0
12.0
V
-fu
nn
el
[s
]
A: Sand [vol.-%] k [-]
Mix Design – Concrete
Paste composition is known
Mortar composition is known
Last remaining unknown: proportion coarse aggregate
Controlled by paste proportion - rest follows automatically
1st basic SCC mix design
With constant paste and coarse aggregate proportions:
Variation mix process
Variation w/c-ratio
Adding steel fibers
25. Conference: "Rheology of Building Materials", Regensburg 15
Mix Design – Concrete
Results: Workability
25. Conference: "Rheology of Building Materials", Regensburg 16
workability range
(w/c)eq = 0.53 c: 306 kg/m³ upm: normal
SF: 30 kg/m³
SF: 60 kg/m³
(w/c)eq = 0.48 c: 320 kg/m³
upm: high
0
5
10
15
20
25
30
60 64 68 72 76 80
V-f
unnel [s
]
Slump-flow [cm]
Overall
Slump-flow [cm]
V-funnel [s]
Density [kg/m³]
Compressive Strength
1d [MPa] 28d [MPa]
Min 64.5 9.3 3936 10.8 61.5
Max 72.0 19.0 4083 13.5 76.1
Mix Design – Concrete
Results: Segregation
25. Conference: "Rheology of Building Materials", Regensburg 17
Conclusion
Basic mix design for further investigations with three additional components: Powder, stabilizer, fibers
Frame conditions
Density
Workability
Segregation
Surface
Strength
Standard SCC procedures for mix design development
Handy, additional tool: Design of Experiments
25. Conference: "Rheology of Building Materials", Regensburg 18
Sources
[1] Okamura, H.; Ozawa, K.: Mix Design for Self-Compacting-Concrete,
Concrete Library of JSCE 25, 1995
[2] Deutscher Ausschuss für Stahlbeton (DAfStb): Selbstverdichtender Beton (SVB- Richtlinie), Beuth Verlag GmbH, 2003
[3] Jossic, L.; Magnin, A.: Traînée et Stabilité d‘Objet en Fluide à Seuil, Les Cahiers de Rhéologie, 2001
[4] Ansley, R. W.; Smith, T. N.: Motion of Spherical Particles in a Bingham Plastic, A.I.Ch.E. Journal 13, 1967
[5] Bethmont, S.; Tailhan, J.; d‘ Aloia-Schwartzentruber, L.; Rossi, P.: Role of the Granular Lattice Solid Fraction in the Stability of Self-Compacting Concrete (SCC), 5th International RILEM Symposium on Self-Compacting Concrete, 2007
[6] Beris, A. N. et al.: Creeping Motion of a Sphere through a Bingham Plastic, Journals of Fluid Mechanics, No. 158, 1985
[7] Vogel, Ruprecht: Zur Tragfähigkeit von Fluiden, R. VOGEL – FORSCHUNG, Labor für Strömungs- und Schüttguttechnik, 2004
[8] Roussel, N.; Coussot, P.: „Fifty-Cent Rheometer“ for Yield Stress Measurements: From Slump to Spreading Flow, The Society of Rheology, Inc., 2005
25. Conference: "Rheology of Building Materials", Regensburg 19
Acknowledgment
Thank you for your attention!
25. Conference: "Rheology of Building Materials", Regensburg Contact: [email protected]