Maria Juenger
The University
of Texas at
Austin
SUPPLEMENTARY
CEMENTITIOUS MATERIALS
AND OTHER
THERMAL CONTROL
STRATEGIES FOR CONCRETE
MODERN CONCRETE
Cement
Water
AirSand
Stone/gravel
eatandys.com
ACI Concrete Terminology definition of SCMs:Inorganic material such as fly ash, silica fume, metakaolin, or ground-
granulated blast-furnace slag that reacts pozzolanically or hydraulically
� Waste
� fly ash
� ground granulated blast
furnace slag
� silica fume
� Natural
� volcanic (glassy)
� tuff (zeolitic)
� sediments (rich in siliceous diatoms)
� diagenic (rich in amorphous silica)
� Processed Natural
� crushed bricks or clay tiles
� calcined clay (e.g. metakaolin)
� rice-husk ash
SUPPLEMENTARY CEMENTITIOUS MATERIALS
...Modern concrete looks a lot like Roman concrete
�Using SCMS we can manipulate:
�Cost
�Workability/Rheology
�Setting
�Heat of hydration
�Early strength
�Late strength
�Resistance to chemical attack
�Environmental impact
THE POWER OF SCMS
� Heat released from the reaction of cement and water
HEAT OF HYDRATION
WHY DOES TEMPERATURE MATTER?
� Heat increases the rate of cement hydration (→ more heat)
� Mechanical property development is af fected by temperature
� f’c, f’t, E, creep, CTE, set time
� Thermal stresses can develop due to temperature gradients,
resulting in cracking risks
� High temperatures during curing can increase risk of cracks due to
delayed ettringite formation (DEF)
0
10
20
30
40
50
60
70
80
0 24 48 72 96 120 144 168
Concrete Age (hours)
Tem
pera
ture
(°C
)
75ºF (24ºC) Placement, 470 lb/cy Cement.
75ºF (24ºC) Placement, 564 lb/cy Cement.
90ºF (32ºC) Placement, 564 lb/cy Cement.
Middle Temperature
Max. Temperature Difference
Temp. Limit for DEF
CALORIMETRY: TOOL TO MEASURE HEAT
OF HYDRATION
� Heat of Solution Calorimetry (ASTM C 186)
� Isothermal Calorimetry
� Adiabatic Calorimetry
� Semi-adiabatic Calorimetry
� Measures the power needed to keep a reference cell at the
same temperature of the sample cell
� Good research tool for understanding cement reaction
kinetics with additives and under dif ferent temperature
conditions
ISOTHERMAL CALORIMETRY
ISOTHERMAL CALORIMETRY:
EFFECT OF TEMPERATURE ON HYDRATION
Ty I Tx Lehigh, 20% Rockdale
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
10.0
0 20,000 40,000 60,000 80,000 100,000 120,000 140,000
Paste age (Seconds)
He
at
Evo
lve
d (
J)
5 C
15 C
23 C
38 C
60 C
23 C
38 C
15 C
60 C
5 C
ISOTHERMAL CALORIMETRY:
EFFECT OF TEMPERATURE ON HYDRATION
Ty I Tx Lehigh, 20% Rockdale
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0 50,000 100,000 150,000 200,000 250,000 300,000
Paste age (Seconds)
Estim
ate
of
De
gre
e o
f H
yd
ratio
n
5 C
15 C
23 C
38 C
60 C
23 C38 C
15 C
60 C
5 C
Cumulative
Heat Evolved
Total Heat
Available
� Some SCMs (Class F fly ash shown here) have no effect on
cement hydration seen by isothermal calorimetry
� Do show that reducing cement content reduces heat of system
ISOTHERMAL CALORIMETRY:
EFFECT OF SCM ON HYDRATION
0
1
2
3
4
5
0 10 20 30 40
No
rma
lize
d H
ea
t F
low
(mW
/g c
em
en
titi
ou
s m
ate
ria
l)
Time (h)
100% I/II
80% I/II + 20% FF1
70% I/II + 30% FF1
60% I/II + 40% FF1
0
1
2
3
4
5
0 10 20 30 40
No
rma
lize
d H
ea
t F
low
(mW
/g
ce
me
nt)
Time (h)
100% I/II
80% I/II + 20% FF1
70% I/II + 30% FF1
60% I/II + 40% FF1
ISOTHERMAL CALORIMETRY:
EFFECT OF SCM ON HYDRATION
0
1
2
3
4
5
0 10 20 30 40
No
rma
lize
d H
ea
t F
low
(mW
/g c
em
en
titi
ou
s m
ate
ria
l)
Time (h)
100% I/II
80% I/II + 20% FF1
70% I/II + 30% FF1
60% I/II + 40% FF1
� Some SCMs can act
as nucleation sites,
enhancing cement
hydration
SCM EFFECTS ON HYDRATION
S. Bishnoi, “Vector Modelling of Hydrating Cement
Microstructure and Kinetics,” EPFL, 2008.
Lothenbach, B., Scrivener, K., Hooton, R.D. (2011)
Supplementary cementitious materials. Cement
and Concrete Research, 41 (12), 1244-1256.
� Some SCMs are more complex
� Class C fly ash influences the hydration of the aluminate
phases
SCM EFFECTS ON HYDRATION
Gurney, L., Bentz, D.P., Sato, T., and Weiss, W.J. , “ Using Limestone to Reduce Set Retardation in High Volume Fly
Ash Mixtures: Improving Constructability for Sustainability,” TRB 2012 Annual Meeting.
Class C fly ash Class F fly ash
With TiO2or limestone of varying median particle sizes added
32.0
50.0
68.0
86.0
104.0
122.0
140.0
158.0
0.0 24.0 48.0 72.0 96.0 120.0
Time from Mixing (Hrs)
Tem
pera
ture
(°F
)
0
10
20
30
40
50
60
70
Tem
pera
ture
(°C
)
Cement Only
40% Class C
Fly Ash
40% Class F
Fly Ash
� Temperature of a concrete cylinder measured in insulated
system with measured rate of heat loss
� Compensate for heat loss to calculate temperature under
an adiabatic condition
15
SEMI-ADIABATIC CALORIMETRY
SCMS – SEMI-ADIABATIC
0.0
2.0
4.0
6.0
8.0
0 10 20 30 40 50
Concrete Age (hours)
Rate
of
Heat
Evo
luti
on
(W
/kg
)
100% C2
80% C2, 20% FF1
70% C2, 30% FF1
60% C2, 40% FF1
0.0
2.0
4.0
6.0
8.0
0 10 20 30 40 50
Concrete Age (hours)
Rate
of H
eat E
volu
tion (W
/kg) 100% C2
80% C2, 20% FC2
70% C2, 30% FC2
60% C2, 40% FC2
CONVERSION OF SEMI-ADIABATIC DATA
TO ADIABATIC DATA
0
1000
2000
3000
4000
5000
6000
7000
8000
9000
10000
0 1 10 100 1000
Test Duration (hours)
Ge
nera
ted
He
at (k
W/m
^3
)
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
Deg
ree
of H
yd
ratio
n
Generated Heat
Degree of Hydration
α(te) = α at equivalent age t
e, α
u= ultimate α, β = hydration slope parameter, τ= hydration time parameter (hrs),
te= equivalent age (hrs)
Qh(t) is the heat released with
time in an adiabatic condition.
Degree of hydration (αt) is the heat released
at time t (Ht), divided by theoretical total heat
that can be released (Hu)
Fit this equation to experimental
degree of hydration data
CONVERSION OF SEMI-ADIABATIC DATA
TO ADIABATIC DATA
Arrhenius equation:
-5
-4
-3
-2
-1
0.0028 0.0030 0.0032 0.0034 0.0036 0.0038
1/Temperature (1/°K)
ln[k(T)] E=21,153 J/mol
Ty I Tx Lehigh, 20% Rockdale
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0 50,000 100,000 150,000 200,000 250,000 300,000
Paste age (Seconds)
Estim
ate
of
De
gre
e o
f H
yd
ratio
n5 C
15 C
23 C
38 C
60 C
23 C38 C
15 C
60 C
5 C
-
500
1,000
1,500
2,000
2,500
3,000
3,500
4,000
4,500
5,000
0 1 10 100 1000
Test Duration (hours)
Gen
era
ted
Heat
(W/m
3)
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
Deg
ree o
f H
yd
rati
on
Generated Heat
Degree of Hydration
70
80
90
100
110
120
130
140
150
160
170
180
190
200
0 24 48 72 96 120 144
Test Duration (hours)
Se
mi-
Ad
iab
ati
c C
on
cre
te T
em
pe
ratu
re (
°F)
Measured
Calculated
False Adiabatic
True Adiabatic
TYPICAL SEMI-ADIABATIC TEST
RESULTS
EFFECTS OF CURING TEMPERATURE
ON ADIABATIC TEMPERATURE RISE
0
10
20
30
40
50
60
1 10 100 1000 10000
Equivalent Age (hours)
Ad
iab
ati
c T
em
pera
ture
Ris
e (
°C)
0
12
24
36
48
60
72
84
96
108
Ad
iab
ati
c T
em
pera
ture
Ris
e (
°F)
29.1 °C
19.0 °C
13.4 °C
28.9 °C
20.7 °C
15.0 °C
100%
Cement C1
30% SCM FF2,
70% Cement C1
EFFECTS OF W/CM ON ADIABATIC
TEMPERATURE RISE
0
10
20
30
40
50
60
1 10 100 1000 10000
Equivalent Age (hours)
Ad
iab
ati
c T
em
pera
ture
Ris
e (
°C)
0
12
24
36
48
60
72
84
96
108
Ad
iab
ati
c T
em
pera
ture
Ris
e (
°F)
w /cm = 0.42
w /cm = 0.40
w /cm = 0.32
EFFECTS OF CEMENTITIOUS MATERIAL
CONTENT ON ADIABATIC TEMPERATURE
RISE
0
10
20
30
40
50
60
1 10 100 1000 10000
Equivalent Age (hours)
Ad
iab
ati
c T
em
pera
ture
Ris
e (
°C)
0
12
24
36
48
60
72
84
96
108
Ad
iab
ati
c T
em
pera
ture
Ris
e (
°F)658 pcy Cementitious (379 kg/m3)
564 pcy Cementitious (325 kg/m3)
470 pcy Cementitious (271 kg/m3)
EFFECTS OF AGGREGATE TYPE ON
ADIABATIC TEMPERATURE RISE
0
10
20
30
40
50
60
1 10 100 1000 10000
Equivalent Age (hours)
Ad
iab
ati
c T
em
pera
ture
Ris
e (
°C)
0
12
24
36
48
60
72
84
96
108
Ad
iab
ati
c T
em
pera
ture
Ris
e (
°F)
Siliceous River Gravel;
Ty F HRWR
Limestone;
Ty F HRWRSiliceous River Gravel;
Ty A&D LRWR
EFFECTS OF CEMENT TYPE ON
ADIABATIC TEMPERATURE RISE
0
10
20
30
40
50
60
1 10 100 1000 10000
Equivalent Age (hours)
Ad
iab
ati
c T
em
pera
ture
Ris
e (
°C)
0
12
24
36
48
60
72
84
96
108
Ad
iab
ati
c T
em
pera
ture
Ris
e (
°F)
100% Cement C1; Ty. F HRWR
100% Cement C2
100% Cement C6
100% Cement C8
100% Cement C9
EFFECT OF FLY ASH ON
ADIABATIC TEMPERATURE RISE
0
10
20
30
40
50
60
1 10 100 1000 10000
Equivalent Age (hours)
Ad
iab
ati
c T
em
pera
ture
Ris
e (
°C)
0
12
24
36
48
60
72
84
96
108
Ad
iab
ati
c T
em
pera
ture
Ris
e (
°F)
80% C2, 20% FF1
70% C2, 30% FF1
60% C2, 40% FF1
100% C2
0
10
20
30
40
50
60
1 10 100 1000 10000
Equivalent Age (hours)
Ad
iab
ati
c T
em
pera
ture
Ris
e (
°C)
0
12
24
36
48
60
72
84
96
108
Ad
iab
ati
c T
em
pera
ture
Ris
e (
°F)
80% C2, 20% FC1
70% C2, 30% FC1
60% C2, 40% FC1
70% C2, 30%FC1 , 0.35% WRRET
100% C2
WHY DOES TEMPERATURE MATTER?
� Heat increases the rate of cement hydration (→ more heat)
� Mechanical property development is af fected by temperature
� f’c, f’t, E, creep, CTE, set time
� Thermal stresses can develop due to temperature gradients,
resulting in cracking risks
� High temperatures during curing can increase risk of cracks due to
delayed ettringite formation (DEF)
0
10
20
30
40
50
60
70
80
0 24 48 72 96 120 144 168
Concrete Age (hours)
Tem
pera
ture
(°C
)
75ºF (24ºC) Placement, 470 lb/cy Cement.
75ºF (24ºC) Placement, 564 lb/cy Cement.
90ºF (32ºC) Placement, 564 lb/cy Cement.
Middle Temperature
Max. Temperature Difference
Temp. Limit for DEF
WWW.TEXASCONCRETEWORKS.COM
� Thermal predictions are made based on:
� Concrete materials and proportions
� Concrete environment (member size and type, formwork, weather)
� Prediction model was built using an extensive database of
calorimetry, concrete mechanical and thermal cracking frame
testing, and field data
� Validated using real, instrumented concrete structures
HOW CONCRETEWORKS WORKS
�Materials
� Concrete mixture
proportions
� SCMs
� Chemical admixtures
� Aggregate and cement
types
�Activation energy is
automatically
calculated, but can
manually override
�Conditions
� Type of concrete
member, size, and shape
�Date and location of
placement (USA)
� can override with manual
temperature inputs
� Fresh concrete
temperature
� Formwork type
� Curing method
INPUT DATA
� Software will proportion concrete mixtures for desired
compressive strength and slump using ACI 211 volumetric
method
� Concrete strength can be predicted using the maturity method
(if you input the calibration constants)
� Corrosion modeling based on inputs of steel type, cover depth,
and exposure class
ADDITIONAL OUTPUTS
EFFECT OF PLACEMENT TIME ON
TEMPERATURE
Max temp
Min temp
Ambient temp
Max temp difference
Temperature development predicted by ConcreteWorks for a 1m x 1m concrete
column placed in Houston, Texas on August 15 using the default concrete mixture
design
Placed at 10am Placed at 10pm
20°C difference
EFFECT OF PLACEMENT TEMPERATURE
ON TEMPERATURE
Max temp
Min temp
Ambient temp
Max temp difference
Placed at 10am Placed at 10am, reduced fresh
temperature
Temperature development predicted by ConcreteWorks for a 1m x 1m concrete
column placed in Houston, Texas on August 15 using the default concrete mixture
design
20°C difference
REDUCING FRESH TEMPERATURE
EFFECT OF SCMS ON TEMPERATURE
Max temp
Min temp
Ambient temp
Max temp difference
Placed at 10am Placed at 10am, 30% Class F fly ash
Temperature development predicted by ConcreteWorks for a 1m x 1m concrete
column placed in Houston, Texas on August 15 using the default concrete mixture
design
20°C difference
EFFECT OF SCMS ON TEMPERATURE
Max temp
Min temp
Ambient temp
Max temp difference
Placed at 10am Placed at 10am, 30% Class C fly ash
Temperature development predicted by ConcreteWorks for a 1m x 1m concrete
column placed in Houston, Texas on August 15 using the default concrete mixture
design
20°C difference
EFFECT OF SCMS ON TEMPERATURE
Max temp
Min temp
Ambient temp
Max temp difference
Placed at 10am Placed at 10am, 30% GGBF Slag
Temperature development predicted by ConcreteWorks for a 1m x 1m concrete
column placed in Houston, Texas on August 15 using the default concrete mixture
design
20°C difference
37
CRACKING RISK EXAMPLE:
5FT X 8FT (1.5 X 2.4M) COLUMN
�Goals:
�Virtually place concrete with at most a medium level
of cracking probability
�Optimize mixture to allow for faster form cycling
�Limestone and siliceous aggregates are available
�Class F fly ash and grade 120 GGBFS are available
�75°F (24°C) placement temperature
�First attempt:
�No SCMs
�Siliceous aggregate (fine and coarse)
�Remove forms after 4 days
38
~40°C
39
TRY CHANGING THE MIXTURE
� Use limestone coarse aggregate
� Use 30% Class F fly ash (will improve workability, and lower
water demand)
� Use a higher dose of Type A low range water reducer – reduce
cement content to 5.5 sacks/yd3 (~300 kg/m3)
� Change placement time to 5pm
� Try dif ferent form removal times
40
~40°C
41
42
74°C 58°C
27°C
43
QUESTIONS?Acknowledgements:
Texas Department of Transportation
Prof. Kevin Folliard (UT Austin)
Prof. Anton Schindler (Auburn University)
Prof. Kyle Riding (Kansas State University)
Dr. Jon Poole (CTL Group)
References:
• Riding, K.A., Poole, J.L., Schindler, A.K., Juenger, M.C.G. and
K.J. Folliard, “Quantification of effects of fly ash type on
concrete early-age cracking,” ACI Materials Journal, 105 [2],
149-155, March-April 2008.
• Poole, J.L., Riding, K.A., Juenger, M.C.G., Folliard, K.J. and
A.K. Schindler, “Effects of supplementary cementitious
materials on apparent activation energy,” Journal of ASTM
International, 7 [9], September 2010.
• Riding, K.A., Poole, J.L., Folliard, K.J., Juenger, M.C.G. and
A.K. Schindler, “Modeling the hydration of cementitious
systems,” ACI Materials Journal, 109 [2] 225-233, March-
April 2012.
MORE REFERENCES:
• Riding, K.A., Poole, J.L., Schindler, A.K., Juenger, M.C.G. and
K.J. Folliard, “Temperature boundary condition models for
concrete bridge members,” ACI Materials Journal, 104 [4],
379-387, July-August 2007.
• Riding, K.A., Poole, J.L., Schindler, A.K., Juenger, M.C.G. and
K.J. Folliard, “Effects of construction time and materials on
bridge deck cracking,” ACI Materials Journal, 106 [5], 448-
454, September-October 2009.
• Riding, K.A., Poole, J.L., Schindler, A.K., Juenger, M.C.G.,
and K.J. Folliard, “Statistical determination of cracking
probability for mass concrete,” ASCE Journal of Materials in
Civil Engineering, accepted.