Indian Journal of Engineering & Materials Sciences
Vol. 21, October 2014, pp. 527-535
Properties of adiabatic temperature rise on concrete considering
cement content and setting time
Kyung-Mo Kooa, Gyu-Yong Kima *, Jae-Kang Yoob & Eui-Bae Leeb
a
Department of Architectural Engineering, Chungnam National University at Daejeon, South Korea
b
DAEWOO Institute of Construction Technology, Suwon, 440-210, Korea
Received 31 October 2013; accepted 30 May 2014
Hydration heat of concrete is closely related to thermal stress and crack, and the adiabatic temperature rise test is a
typical testing method for measuring hydration heat. The aim of this study is to investigate the effect of cement content and
placing temperature on adiabatic temperature rise of concrete. To investigate the behavior of adiabatic temperature rise of
concrete, it was decided to set binder content taking into account the mixing temperature of concrete and the placing
temperature of concrete that are 25ºC and 35ºC, respectively. Cement content has a linear relation with the maximum value
of adiabatic temperature rise (K) and reaction factor (r). The temperature rising ratio of the specimen with placing
temperature 35ºC rapidly increased compared to that of the specimen with placing temperature 25ºC, but the maximum
value of adiabatic temperature rise between placing temperatures 25ºC and 35ºC are not significantly different. Furthermore,
it is found that the starting time of hydration heat (t0) after the placement of concrete has a high correlation with the final
setting time. It is necessary to analyze the effect of adiabatic temperature rise by taking the final setting time into
consideration.
Keywords: Cement content, Setting time, Mixing temperature, Adiabatic temperature rise
Generally, concrete experiences a significant amount
of hydration heat during cement hydration reactions
that start immediately when cement is mixed with
water. Though hydration heat is observed in all
types of concrete, it can be particularly high in
high-performance concrete having low water-tobinder ratio. Hydration heat of cement can lead to
surface-breaking cracks when base friction or other
restraints occur. The presence of surface-breaking
cracks in concrete structures may not necessarily
imply structural failures, but may cause various
durability and serviceability issues, e.g., stiffness
reduction, infiltration of water or deleterious
materials, corrosion of reinforcing steels, which
may finally lead to early malfunction of concrete
structures. Therefore, hydration heat of concrete is
an important design issue and effective cooling
methods should be developed to avoid the damage
induced by temperature cracks.
The other major cause for high hydration heat
of concrete is the temperature of the surrounding
environment. A high environment temperature
leads to a high placing temperature. The high
placing temperature causes maximum temperature
——————
*Corresponding author (E-mail: gyuyongkim@cnu.ac.kr)
rise and leads temperature rising velocity of concrete
at early ages. It increases the possibility of occurrence
of cracks in concrete. In Korea1, when the average
temperature exceeds 25ºC, the use of hot weather
concrete is recommended and the placing temperature
is limited to 35ºC. It is important to predict
and manage hydration heat of concrete in advance
by considering the environment temperature and/or
the placing temperature.
Researchers in the field of material science have
made great efforts to find an effective reduction
method of hydration heat of concrete. The reduction
of hydration heat of concrete is achieved by the four
methods:
(i) Postcooling of concrete structures: Water pipe
cooling is now widely adopted to control the
temperature of dam concrete2. However, the large
temperature difference between water and concrete
causes large temperature stresses around the cooling
pipe, and may result in serious cracks, which are
harmful for the concrete structures3-6.
(ii) Precooling of concrete materials: The first use of
precooling of concrete materials to reduce the
maximum temperature of concrete was by the Corps
of Engineers during the construction of Norfork
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INDIAN J. ENG. MATER. SCI., OCTOBER 2014
Dam in the early 1940s. A part of the mixing water
was introduced into the concrete mixture as crushed
ice so that the temperature in place fresh concrete
was limited to about 6ºC7. Recently, precooling
methods such as aggregate cooling by spraying
liquid nitrogen, spraying liquid nitrogen on concrete
after mixing, vacuum cooling of aggregate by
evaporation heat, and mixing water with cold water
or ice are being adopted.
(iii) Use of smart materials (e.g., phase change
materials or setting retarders): Since 1990s, many
works have been carried out to reduce the interior
temperature rise of mass concrete with PCM. Some
researches8-10 found that after PCM was blended
with cement, the temperature peak was reduced and
the appearance time of temperature peak was
delayed; however, the strength of concrete was also
decreased. Meanwhile, using a setting retarder is an
effective way to reduce the temperature peak or
temperature rise velocity by retarding the hydration
reaction of cement or the reaction velocity. Recently,
research and development of micro-encapsulated
retarders on for achieving the stepwise setting retard
effect is gaining traction.
(iv) Replacing normal Portland cement with other
cementitious additions (e.g., fly ash and/or
blast furnace slag): Technical advantages of
using fly ash and slag concrete compared to plain
PC concrete relate to low heat of hydration, which
is of particular importance in the case of massive
concrete elements11,12, increased durability of
reinforced concrete in the marine environment,
and increased long-term strength. A recent study
by Vejmelkova et al.13 showed that some of the
positive characteristics of slag concrete can
be obtained even at replacement levels as low as
10% or 20%.
The adiabatic temperature rise history varies
according to the mix of concrete (see Fig. 1).
However, the result of comprehensive analysis of
reaction factor and adiabatic temperature rise is
insufficient. This study consistently sets unit water
content and the amount of binders to review
the properties of adiabatic temperature rise of
high-strength concrete on the amount of cement as
well as the types and replacement rates of admixtures.
To consider the effects of the environment
temperature on the hydration temperature, the
adiabatic temperature test of concrete was carried out
setting the placing temperature and the initial curing
temperature to 25ºC and 35ºC, respectively.
In addition, the relation between the starting time
of hydration heat and the setting time is investigated
to analyze the adiabatic temperature rise equation
with respect to the amount of cement.
The adiabatic temperature rise test is carried out to
estimate the hydration property of concrete. The result
obtained on the basis of the adiabatic temperature rise
test is presented in Eq. (1)1:
Q = K (1 − e − rt )
… (1)
where Q is the adiabatic temperature rise at age
t (ºC), K is the maximum amount of the adiabatic
temperature rise (ºC), r is the reaction factor (ºC/h),
t is the age (days), and t0 is the starting time of
hydration heat (days).
Fig. 1 – Schematic of adiabatic temperature rise by various
factor
KOO et al: ADIABATIC TEMPERATURE RISE ON CONCRETE
529
Table 1 – Experimental plan
ID
W/B
(%)
WB40-OPC
WB34-OPC
WB29-OPC
WB29-F20
WB29-F35
WB29-S40
WB29-S70
Unit
Binder
(kg/m3)
40
34
400.0
470.6
551.7
29
SF
Replacement
(B×%)
FA
BFS
5
5
5
5
5
20
35
-
40
70
Placing
temperature
(°C)
25±1
35±1
* SF : silica fume, FA : fly ash, BFS : blast furnace slag powder
W/B : water-cementitious material ratio
F20 : Binders with OPC 80% + fly ash 20%
F35 : Binders with OPC 65% + fly ash 35%
S40 : Binders with OPC 60% + blast furnace slag 40%
S70 : Binders with OPC 30% + blast furnace slag 70%
Table 2 – Mixing of concrete
ID
W/B
(%)
S/a
W
WB 40-OPC
40
43
160
WB 34-OPC
34
48
160
WB 29-OPC
29
48
160
WB 29-F20
160
WB 29-F35
160
WB 29-S40
160
WB 29-S70
160
* S/a : sand percentage, W : water, C : cement,
G : coarse aggregate, S : fine aggregate
C
400
470
524
413
331
303
137
Experimental Procedure
Test specimens and material properties
Test specimens made from high-strength concrete
were prepared in the laboratory. The high-strength
concrete was made from mixing proportions having
29, 34, and 40% of the water-to-binder ratio and 400,
470, and 551 kg/m3 of cement. The specifications
of the mixing proportions are summarized in Table 1.
The main variables of experiments in this
study include the W/B (40%, 34%, and 29%),
replacement ratio of the mineral admixture (fly ash
20% and 35% of the total binder weight; blast
furnace slag powder 40% and 70% of the total
binder weight) and placing temperature (25ºC and
35ºC). In addition, 5% silica fume was mixed for
developing the compression strength in the W/B
with 29% concrete mixture. Experimental variables
are given in Table 2.
Unit weight (kg/m3)
SF
FA
BFS
27
27
110
27
193
27
220
27
386
G
1046
924
885
864
848
877
870
S
762
824
776
771
757
782
776
SP
(B×%)
0.60
1.20
1.40
1.25
1.10
0.90
0.80
Materials of concrete used in this study are
ordinary Portland cement (density: 3.15 g/cm3,
fineness: 3,770 cm2/g), desalting sand (density:
2.54 g/cm3, fineness modulus: 3.05, absorption ratio:
1.01), crushed aggregate (density: 2.65g/cm3, fineness
modulus: 6.02, absorption ratio: 1.39), silica fume
(density: 2.50 g/cm3, fineness: 200,000 cm2/g), fly
ash (density: 2.20 g/cm3, fineness: 3,000 cm2/g),
blast furnace slag powder (density: 2.91 g/cm3,
fineness: 4,000 cm2/g) and high range water reducer
(polycarboxylic acid type).
Early-age properties
In this study, slump-flow, air-content, and setting
time were tested in accordance with ASTM C1611M
(standard test method for slump flow of selfconsolidating concrete), ASTM C231M (standard
test method for air content of fresh concrete by
the pressure method), and ASTM C403M (standard
INDIAN J. ENG. MATER. SCI., OCTOBER 2014
530
test method for time of setting of concrete mixtures
by penetration resistance) respectively to investigate
the effects of the placing temperature and the mineral
admixture on the early-age properties of concrete.
In this study, a superplasticizer was added as a
supplement to make sure minimum fluidity (target
slump flow 600±50mm) of fresh concrete.
Adiabatic temperature rise test
The temperature of the used materials to satisfy
the mixing temperature requirement of concrete was
calculated using Eq. (2)14.
T=
0.22(TaWa + TcWc ) + TwWw + TaWwa
0.22(Wa + Wc ) + Ww + Wwa
… (2)
where, Ta is the temperature of aggregate, Tc is the
temperature of cement, Tw is the temperature of water,
Wa is the dry-rodded weight of aggregate, Wc is the
dry-rodded weight of cement, Ww is the dry-rodded
weight of water, and Wwa is the absorption ratio of
aggregate.
Concrete that reached the target temperature was
placed on the adiabatic temperature rise test device
after mixing. The adiabatic temperature in concrete
specimens was monitored by using a thermocouple.
Measurements were taken at the interval of ten
minutes until the internal temperature converged.
The volume of the mold of the specimens was 50 L.
Results and Discussion
Fresh concrete
It was observed that the W/B and the mineral
admixture affect the early-age properties of concrete
such as setting time, slump flow and air content.
First, the role of the W/B increases and the mineral
admixture replacement ratio was demonstrated
to be effective for delaying the initial and final
setting times as shown in Fig. 2. In concrete
specimens with 34% and 40% of the W/B, setting
times were delayed by approximately half an hour
compared to that in the specimen with 29% W/B.
Furthermore, the delaying effect by using the fly ash
and the blast furnace slag significantly increased as
the replacement ratio of the mineral admixture
increased. Especially, in the concrete specimen
with 70% blast furnace slag, setting times were
delayed by about 8 h compared to the specimen
of OPC (W/B 29%). In contrast, the accelerating
effect on the setting time was observed as the placing
temperature was increased from 25ºC to 35ºC.
In addition, it was found that the slump flow tends
to increase with the increase of the amount of the fly
ash and blast furnace slag in concrete specimens.
Accordingly, the amount of the superplasticizer to
meet the target slump flow requirement decreases.
This phenomenon can be explained by the ball
bearing effect observed as the fly ash consists of
spherical particles. However, the effect of fluidity by
the BFS particles is due to another cause. The fluidity
of concrete is associated with the morphological
characteristics of the BFS particles. At the initial stage
of cement hydration, BFS particles are packed
uniformly on the surface of cement particles, which
retard and decrease mutual combination of early
hydration products. This is somewhat similar to the
effect of water reducers and increases the fluidity of
mortar. In other words, glass of SiO2 constitutes BFS
particles that reduce the frictional force among
particles. The smoother the surface of particles, the
better was the fluidity of mortar15.
Next, air content tends to decrease with the
increase of the amount of the mineral admixture.
However, the variability of air content does
not appear to have a significant impact on the
performance of concrete.
Adiabatic temperature of concrete
Figure 3 shows the adiabatic temperature in
concrete with respect to the W/B and the amount of
admixture. The placing temperature was set with 25ºC
and 35ºC. The adiabatic temperature of all specimens
converged in two days after concrete placement.
Fig. 2 – Setting time by mixing condition and placing
temperature
KOO et al: ADIABATIC TEMPERATURE RISE ON CONCRETE
531
Fig. 3 – Adiabatic temperature history
Generally, it is reported that the convergence time of
maximum adiabatic temperature by the adiabatic
temperature rise test takes between 5 and 7 days. In this
study, however, the phenomenon that the convergence
time decreases by the use of high-strength concrete
was confirmed. It was observed that increasing the
W/B and using the admixture tend to decrease the
maximum adiabatic temperature and the temperature
rising velocity at early ages. For the specimens with
placing temperature 25ºC, the measured maximum
adiabatic temperature values of WB34-OPC and
WB40-OPC were 75.8ºC, and 68.6ºC, respectively,
which were reduced by approximately 3.7% and 12.9%
compared to that of WB29-OPC (78.7ºC). Furthermore,
the maximum adiabatic temperature values of
WB29-F20, WB29-F35, WB29-S40, and WB29-S70
were reduced by approximately 9.6%, 12.2%, 12.9%,
and 32.0% compared to that of WB29-OPC. Similarly,
in the specimens with placing temperature 35ºC, it is
confirmed that the increase of the W/B and the use
of the admixture led to decrease of the maximum
adiabatic temperature values in concrete.
In addition, the maximum adiabatic temperature
of all the specimens with placing temperature
35ºC was between 60.5ºC and 89.1ºC, which were
Fig. 4 – Relation between cement content and maximum
temperature in concrete
increased by approximately 9.0%-14.9% compared
to that of WB29-OPC with the placing temperature
of 25ºC. In other words, the placing temperature is
an important factor that has a significant effect on the
rise of adiabatic temperature.
Figure 4 shows the relationship between the cement
content and the maximum adiabatic temperature in
532
INDIAN J. ENG. MATER. SCI., OCTOBER 2014
Fig. 5 – Adiabatic temperature rise by concrete mixing and placing temperature
concrete. It was found that a linear relationship
exists between the maximum adiabatic temperature
and the cement content. It means that the cement
content, exclusive of the amount of admixture,
in concrete contributes to the maximum
temperature.
Adiabatic temperature rise and temperature rising ratio
Figure 5 shows the adiabatic temperature rise
according to the concrete mix and the placing
temperature. It was found that the temperature rising
ratio with placing temperature 35ºC in a day was
higher than that of the specimens with placing
temperature 25ºC. On the other hand, the adiabatic
temperature rise of all specimens with placing
temperature 35ºC was lower than that of the specimens
with placing temperature 25ºC compared to the
tendency of the maximum adiabatic temperature
in concrete. The hydration reaction in early ages is
activated as the placing temperature in concrete
increases. Although an active hydration reaction
increases the temperature rising ratio in concrete,
the adiabatic temperature rise decreases. It can be
explained by adverse effects of a high early temperature
that Verbeck and Helmuth suggested. According to
them, the rapid initial rate of hydration at higher
temperatures retards subsequent hydration and produces
a non-uniform distribution of the products of hydration
within the paste. The reason for this is that at the high
initial rate of hydration, there is insufficient time
available for the diffusion of the products of hydration
away from the cement particle and for a uniform
precipitation in the interstitial space. As a result,
a high concentration of the products of hydration
is built up in the vicinity of the hydrating particles,
and this retards subsequent hydration. Therefore,
hydration reaction of cement particles cannot be
completed appropriately, and this has negative effects
on the long-term strength of concrete16,17.
Fig. 6 – The division of adiabatic temperature rise history
Analysis of adiabatic temperature rise history
The adiabatic temperature rise history
As shown in Figure 6, the adiabatic temperature rise
history is divided into three sections. Hydration heat
almost cannot be seen in section 1. Generally, the
hydration heat in concrete tends to begin in a short
space of time after placement. To reproduce an accurate
adiabatic temperature rise history, the time (t0) of the
section 1 needs to be clear. In this study, considering
t0 of section 1, Eq. (1) was modified to Eq. (3) as:
Q = K (1 − e − r (t − t 0 ) )
… (3)
where, Q is the adiabatic temperature rise at age
t (ºC), K is the maximum value of adiabatic
temperature rise (ºC), r is the reaction factor (ºC/h),
t is the age (days), and t0 is the starting time of
hydration heat (days).
The constant t0 that has the highest reliability was
selected through regression analysis. In section 1, the
temperature rise was regarded as zero. In practice, the
temperature increased slightly in this section before t0,
KOO et al: ADIABATIC TEMPERATURE RISE ON CONCRETE
but it was considered that ignoring the temperature
rise in section 1 is effective to increase the reliability
of the reaction factor (r).
The relationship between the time (t0) of section
1 and the setting time was analyzed. The temperature
increases rapidly in the section 2 of the adiabatic
temperature rise history. This section is linked to
'reaction factor (a constant r)' of Eq. (3).
In addition, since it is behavior of concrete within
a day, it is concluded that reaction factor (r) is related
to placing temperature of early ages. Lastly, the
temperature converges in section 3. The temperature
started from placing temperature converges on the
maximum value of adiabatic temperature rise and it
maintains the value. The maximum value of adiabatic
temperature rise is constant (K) in Eq. (3).
The maximum value of adiabatic temperature rise (K)
Figure 7 presents the relation between the maximum
value of adiabatic temperature rise (K) and the cement
content based on the resulting data in this study.
Generally, it is reported1 that the maximum value of
adiabatic temperature rise (K) is proportional to the
binder content containing mineral admixture under
similar binder conditions2. In this study, it was found
that there exists a linear relationship between the
maximum value of adiabatic temperature rise (K) and
the cement content excluding admixtures in concrete
in all concrete mixes. In other words, it can be
explained that it is possible to predict the maximum
value of adiabatic temperature rise (K) from the cement
content regardless of the mineral admixture type and
the W/B in concrete.
It was observed that the maximum value of
adiabatic temperature rise (K) of a specimen
with placing temperature 35ºC is approximately
Fig. 7 – Relation between the maximum value of adiabatic
temperature rise (K) and the cement content in concrete mixing
533
2~4ºC lower than that of a specimen with placing
temperature 25ºC.
Reaction factor (r)
It was found that the placing temperature affects
the temperature rising ratio of concrete (see Fig. 5).
A high placing temperature was demonstrated to
be effective for making the reaction factor (r) high
as shown in Fig. 8. Furthermore, it was observed that
the reaction factor rises linearly with the cement
content excluding admixtures in concrete.
Accordingly, the use of admixture and the
management of the placing temperature in concrete
are important factors to control the reaction factor at
early ages.
Starting time of hydration heat (t0)
Figure 9 shows the starting time of hydration heat
(t0) according to the cement content. Increasing the
placing temperature and cement content delayed the
starting time of hydration heat (t0) for concrete.
Fig. 8 – Relation between the reaction factor (r) and the cement
content in concrete mixing
Fig. 9 – Relation between the starting time of hydration heat (t0)
and the cement content in concrete mixing
INDIAN J. ENG. MATER. SCI., OCTOBER 2014
534
Figure 10 presents the relationship between the
setting time and the starting time of hydration heat
(t0). Through experimental research, in high-strength
concrete, it was found that the starting time of
hydration heat (t0) has a close correlation with the
final setting time. Through the final setting time
of concrete, the early-age behavior of the adiabatic
temperature rise history such as the starting time of
hydration heat (t0) can be predicted.
Verification of K, r and t0
In this study, adiabatic temperature rise properties of
concrete according to W/B and concrete content were
reviewed. Results of the adiabatic temperature rise test
obtained using the Eq. (3) and concrete mixing that has
a similar range were compared. Additionally, the
reliability of test results was reviewed.
Concrete mixing details and the setting time are
given in Table 3. Concrete mixing details presented
are obtained from construction sites in Korea. The
concrete was made from mixing proportions with
water-to-binder ratios of 23.8% and 44%. The
adiabatic temperature rise test was conducted by the
construction company that designed concrete mixing.
The placing temperature is 25°C, and the setting times
are given in Table 3.
The constants K and r are given by the Eqs (4) and
(5) (the placing temperature is 25°C):
K = 0.0589C + 22.8.18
…(4)
r = 0.0045C + 2.1997
where, C is the cement content (kg/m3)
…(5)
Figure 11 shows the experimental results
obtained by the adiabatic temperature rise test
and the calculated results obtained using the
prediction model. The constant t0 set by the
final setting time of concrete is almost similar
to the section without hydration heat. In addition,
it is confirmed that the adiabatic temperature rise
history represented by K and r is approximately
equal to the experimental values.
Table 3 – Mixing of concrete for verification and
setting time
ID
W/B
(%)
Unit weight
Setting time
(kg/m3)
(h)
W C SF FA BFS G S Initial Final
WB 24- 40 155 481 39 130 - 745 835 5.2 7.4
OPC
WB 44- 34 165 105 - - 246 845 1000 8.1 12.1
OPC
Fig. 10 – Relation between the starting time of hydration
heat (t0) and the setting time in concrete
Fig. 11 – Experimental result by adiabatic temperature rise test
and calculated result by prediction model
KOO et al: ADIABATIC TEMPERATURE RISE ON CONCRETE
In conclusion, it is confirmed that the prediction
model and the approach method on the constant
(K, r, t0) in this thesis have sufficient reliability.
In other words, through an analysis of the cement
content and the final setting time of concrete, the
behavior of adiabatic temperature rise history can
be predicted.
Conclusions
In this study, the effects of cement content,
placing temperature, and setting time on the
adiabatic temperature rise history in concrete were
investigated. The conclusions drawn from this
study are as follows:
535
(iv) In conclusion, it is possible to predict the
behavior of adiabatic temperature rise history
from the cement (OPC) content and the setting
time.
Acknowledgements
This research was supported by the Basic Science
Research Program through the National Research
Foundation of Korea (NRF) funded by the Ministry
of Education (2014R1A1A2008385). The authors
were supported by the BK21 Plus Program
(Chungnam National University) and DAEWOO
Institute of Construction Technology.
References
(i)
It was found that the maximum adiabatic
temperature, maximum value of adiabatic
temperature rise (K), and reaction factor (r)
have a high correlation with the cement content
excluding admixtures of unit binder content.
It can be considered that the cement content
in concrete mixing is important factor to
analyze the properties of adiabatic temperature
rise history.
(ii) In this study, the adiabatic temperature rise
history is divided into three sections: (a) the
section of no hydration heat, (b) the section
of rapid temperature rise, and (c) the section
of maintain of maximum temperature. Among
these, the time of section 1 (or the starting time
of hydration heat (t0)) has a close correlation
with the final setting time. Therefore, it means
that the starting time of hydration heat (t0)
can be set with the final setting time of
concrete.
(iii) The placing temperature accelerates the setting
time and the starting time of hydration heat (t0).
A high placing temperature was demonstrated
to be effective for making the reaction factor
(r) high. However, the contribution of placing
temperature to the maximum value of adiabatic
temperature rise (K) of concrete was low.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
Korea Concrete Institute: 'Standard Concrete Specification,
Ch 18 (Mass Concrete', Seoul, Korea), 2009, 202-216.
Tohru K & Sunao N, ACI, 93 (1) (1996) 32-37.
Zhu B F, Wu L S & Zhang G X, Water Resour Hydropower
Eng, 40 (7) (2009) 22-31.
4 Zhu B F, Water Resour Hydropower Eng, 40(1) (2009)
44-50.
Liu G Y & Zhu Y M, Hongshui River, 25(1) (2006) 16-19
MaY F, ZhuY M, Cao W M & Ning Y, J Hydraulic Eng,
37(8) (2006) 963-968.
Mehta P Kumar & Monteiro Paulo J M, Concrete:
microstructure, properties, and materials- 12.9 Mass
Concrete, 3rd ed, (New York, U.S.A), 531-541.
Pasupathy A & Velraj R, Energy Build, 40(3) (2008)
193-203.
Xing J J & Guan X J, Res Appl Build Master, (6) (2008)
4-6.
Yang Y K, Zhang X & Lu S L, China Concr Cem Prod, (5)
(2007) 9-11.
Alshamsi A M, Cem Concr Res, 27(12) (1997) 1851-1859.
Ballim Y & Graham P C, Mater Struct, 42 (2009) 803-811.
Vejmelkova E, Pavlikova M, Keršner Z, Rovnanikova P,
Ondracek M, Sedlmajer M, et al., Constr Build Mater,
23 (2009) 2237-2245.
Guide to Hot Weather Concreting, (American Concrete
Institute), ACI 305 R-10, 2010.
Wan H, Shui Z & Lin Z, Cem Concr Res, 34(1) (2004)
133-137.
Verbeck G J & Helmuth R A, Structures and physical
properties of cement paste, Proc. 5th Int Symp on the
Chemistry of Cement, Tokyo, 3 (1968) 1-32.
Verbeck G J & Copeland L E, Some physical and chemical
aspects of high-pressure steam curing, Menzel Symp on
High-Pressure Steam Curing, ACI SP-32, 1972, 1-13.