Updated with power absorption for High-Energy Mixing (HEM) and High Shear Mixing (HSM)

1. High Shear Mixing and High-Energy Mixing in Two-Stage mixing concrete
M. Yahg: High Shear Mixing (HSM)
Vladlen Fridman: High-Energy Mixing
(HEM)
Cement + Water (Slurry) Cement + Water (Slurry) Cement + Water + Sand
(Mortar)
Main result of
method
“Disperse cohesive powders, such as cement powder”, “increase area of interface
between the components”, “inhomogeneities are reduced”
Increase C-S-H gel formation, accelerate cement
hydration.
Main idea of
method
Provide in “laminar shear flow” Shear stress and Shear rate to break cement
agglomerates, “
Provide increased Energy absorption to activate cement
hydration and create nanostructure of CSH gel (bottom-
up approach in Nanotechnology)
Parameters of
mixing
1/2hp (368wt) Osterizer blender, Speed above 3000 rpm, Energy about 5.5KJ/kg, time
1 min. (M. Yang, H.M. Jennings “Influences of Mixing Methods on the
Microstructure And Rheological Behavior of cement Paste”, Elsevier Science Inc.,
1995
Energy 5.0-400 KJ/kg, Power 30-600wt/kg, quasi
laminar flow, Re number 20-800, Np= 0.1-4.0, time 3-5
min. (Vladlen Fridman, US 20130305963)
Comparison of
Energy
absorption in
Mixing process
0
50
100
150
200
250
0 50 100 150 200 250 300
NetPowerwatt/kg
Time of mixing, sec
Specific Net Power
HSM Slurry
HEM Slurry
HEM Mortar

2. Parameters for
Processes
fulfilled
in lab.
conditions
HSM
W/C = 0.37
Absorbed Energy 4432 J/kg, average Re number = 1718, average Np = 0.027
HEM
W/C = 0.37
Absorbed Energy 32220
J/kg, average
Re number = 529, average
Power number
Np = 0.15
HEM
W/C/S = 0.39/1/2
Absorbed Energy 32108
J/kg,
Average Re number
110.5
Average Power number
Np = 0.86
Rate of
Hardening
With
Penetration
Resistance
Method
(Tuthill
and Cordon)
High-Energy Mixed
Slurry W/C=0.37
Bleeding water 0.18%
of total quantity.
Syneresis visible
on samples magnified
x100
High-Energy mixed mortar W/C/S = 0.39/1/2,
High-Shear mixed slurry W/C=0.37 Bleeding water 0.0 %
Bleeding water 0.58% of total water Macro-syneresis of HEM activated mortar
(evidence of C-S-H gel formation)
Allowed quantity of Fly Ash
without loss of concrete strength
HSM (C+W)
No more than 15% of cement quantity -----
HEM (C+W+S)
Up to 50% of cement quantity
0
1000
2000
3000
4000
5000
6000
0 2 4 6 8 10
Penetrationresistance,psi
Time, hours
Control
HSM
0
2000
4000
6000
8000
0 5 10 15
penetrationresistance,psi Time, hours
control
HEM
0
2000
4000
6000
8000
10000
0 2 4 6 8 10
Penetretionresistance,psi
Time, hours
control
HEM

3. Power absorption in activation with two methods: HEM and HSM
a) Cement – Water mixes
High-Shear
Mixing, η=55%
Re=4874,
N=7115,W/C=0.43
High-Shear
Mixing, η=34%
N=5615, Re=1718
W/C=0.36
High-Shear
Mixing, η=10%
N=3045rpm,Re=580
W/C=0.37
0
50
100
150
200
250
300
350
0 1000 2000 3000 4000 5000 6000
NetPower,wt/kg
Re number
Power absorption by the cement-water mixtures
High-Energy
Mixing, η = 10-54%
C-S-H gel Creation
Re=20-800,
N=600-3000 rpm,
w/c=0.26-0.40

4. b) Cement – Sand - Water mixes
High-Shear
Mixing, η=10%
N=3045rpm,Re=580
W/C=0.37
0
50
100
150
200
250
300
350
0 1000 2000 3000 4000 5000 6000
NetPowerwt/kg
Re number
Power absorption by the cement-sand-water mixtures
High-Shear
mixing,η = 55%,
Re=4874,
N=7115,W/C=0.43
High-Shear
Mixing,η = 34%
N=5615, Re=1718
W/C=0.36
High-Energy
Mixing, η=10-55%
C-S-H gel creation,
Re=20-800
N=600-3000rpm,
W/C=0.0.36-0.58
C/S=0.25-3.0