Note: Descriptions are shown in the official language in which they were submitted.
CA 02237702 1998-OS-14
150P14CA
IN THE UNITED STATES PATENT AND TRADEMARK OFFICE
PATENT APPLICATION
IMPROVED CEMENTITIOUS COMPOSITIONS
A. Background of the Invention
1. Field of the Invention
This invention relates to improvements in cementitious compositions and in
particular the use of an admixture in such compositions. The term
"cementitious compositions",
as used herein, is intended to mean compositions which set and harden by
chemical interaction
with water and are capable of doing so under water. These compositions include
cementitious
waterproofings, toppings, protective coatings, and the like as well as
mixtures with aggregates
and water such as concrete, mortar, grout and products made therefrom.
2. Description of the Prior Art
In the construction industry, and particularly in the repair of concrete
structures
such as highways and structural walls and platforms, and the filling of voids
and holes to form
stable underpinnings or foundations for machinery and heavy equipment, there
has been a need
for cementitious compositions which sets into a hard mass with sufficient
early strength to
withstand applied stresses and loads and which does so in an accelerated
period of time and with
an increased rate of heat evolution. There have been numerous attempts in the
past to formulate
admixtures for cementitious compositions with these characteristics, but such
attempts have met
with only limited success. The admixtures employed often produced undesirable
properties and
CA 02237702 1998-OS-14
side effects such as corrosion of reinforcing steel in concrete by admixtures
containing chloride,
insufficient early strength gain, and long-term strength degradation. Most
admixtures developed
for high alumina cements were ineffective for Portland cements, while
admixtures produced for
Portland cement were unsatisfactory for high alumina cements.
Examples of prior attempts at producing satisfactory admixtures are described
in
M. Shimizu, T. Tano, K. Uchida and N. Kitaoka, "Concrete Additive" - Japan
Kokai 79 50528,
Apr. 20, 1979; Chem Abstr., 91 128011 { 1979) and in V.I. Remiznikova, T.I.
Astrova, V.P.
Schmidt, M.S. Nizamov, V.N. Popko, V.P. Zuey, M.A. Loginov and A.V.
Beinarovich, "Complex
Additive for a Cement-Concrete Mixture" - U.S.S.R. 697, 436, Nov. 15, 1979;
Chem Abstr., 92
81279 ( 1980).
Accordingly, it is an object of the present invention to provide a
cementitious
composition including an admixture which when mixed with water will set within
an accelerated
period of time into a hard mass of increased early strength.
Another object of the present invention is to provide a cementitious
composition
including an admixture which when mixed with water will set within an
accelerated period of
time into a hard mass of increased early strength and which has an increased
average rate of heat
evolution.
An additional object of the present invention is to provide a cementitious
composition including an admixture which when mixed with water will set within
an accelerated
period of time into a hard mass of increased early strength and which has an
increased average
rate of heat evolution and includes a plasticizing (water reducing) and
defoaming agent.
A still further object of the present invention is to provide a cementitious
-2-
CA 02237702 1998-OS-14
composition including an admixture which when mixed with water will set within
an accelerated
period of time into a hard mass of increased early strength and which has an
increased average
rate of heat evolution and includes an air releasing and/or gas generating
agent.
A still further object of the present invention is to provide a cementitious
composition including an admixture which when mixed with water will set within
an accelerated
period of time into a hard mass of increased early strength and which has an
increased average
rate of heat evolution and includes an air entraining agent.
A still further object of the present invention is to provide a cementitious
composition including an admixture which when mixed with water will set within
an accelerated
period of time into a hard mass of increased early strength and which has an
increased average
rate of heat evolution and includes a corrosion inhibitor.
A still further object of the present invention is to provide a cementitious
composition including an admixture which when mixed with water will set within
an accelerated
period of time into a hard mass of increased early strength and which has an
increased average
rate of heat evolution and includes a mineral admixture.
SUMMARY OF THE INVENTION
The foregoing objects are achieved according to the present invention by the
discovery of a novel admixture which consists of a combination of aluminum
oxide, silicon
dioxide and zirconium oxide in the proportions specified below. In addition to
the admixture,
the cementitious composition includes sand and water, high alumina cement or
portland cement
or a combination of both high alumina cement and portland cement. Plasticizing
and defoaming
-3-
CA 02237702 1998-OS-14
agents, air releasing and/or gas generating agents, air entraining agents,
corrosion inhibitors and
mineral admixtures may also be used with the cementitious compositions of the
present invention.
The range of the aluminum oxide used in the admixture of the present invention
is between 70 and 96%, by weight, of the total admixture, the range of silicon
dioxide is between
2 to 15%, by weight, of the total admixture, and the range of zirconium oxide
is between 2 to
15%, by weight, of the total admixture.
The foregoing and other objects, features and advantages of the invention will
be
further apparent from the following detailed description thereof and the
accompanying claims.
Detailed Description of the
Preferred Embodiment
The invention is best illustrated by the following experiments and the results
of
the experiments set forth in the Tables below. In the following discussion,
percentages are by
weight unless otherwise indicated. In each control specimen and experiment
discussed below,
the water was mixed with the dry mixture and the data was then recorded. In
all the control
specimens and experiments, with the exception of experiments 16 and 17, the
water content of
the composition comprised 20% of the weight of the dry materials.
The Control Specimen for Experiments 1, 2 and 3
The same control specimen was utilized for Experiments 1, 2 and 3. The control
specimen consisted of mixing Secar 51 high alumina cement, sold by Lafarge
Calcium
Aluminates, Inc., with sand and water. The dry mixture of the control specimen
included equal
parts of Secar 51 high alumina cement and sand.
-4-
CA 02237702 1998-OS-14
Experiment 1
In Experiment 1, the percentage of the Secar 51 high alumina cement remained
the same as the control specimen, i.e., 50%; however, the sand content was
reduced to 47.5% and
the admixture in the amount of 2.5% of the total mixture was added. The
admixture comprised
aluminum oxide, A 1203, in the amount of 2.1 % of the total mixture; silicon
dioxide, Si02, in the
amount of .22% of the total mixture; zirconium oxide, Zr02, in the amount of
.18% of the total
mixture. As a percentage of the admixture, the aluminum oxide comprised 84% of
the
admixture, the silicon dioxide comprised 8.8% of the admixture and the
zirconium oxide
comprised 7.2% of the admixture. With respect to the results of Experiment l,
both the initial
and final set time decreased compared to the control specimen, the early (up
to one day)
compressive strength increased compared to the control specimen, and both the
exotherm peak
and average rate of temperature growth increased compared to the control
specimen.
Experiment 2
In Experiment 2, the percentage of the Secar 51 high alumina remained at 50%
of the dry mixture, however, the sand content was further reduced to 45%. In
this experiment,
the percentage of the admixture was increased two-fold, from 2.5% to 5%, and
each of the
components of the admixture, the aluminum oxide, silicon dioxide and zirconium
oxide was also
increased two-fold i.e., the aluminum oxide was increased to 4.2%; the silicon
dioxide was
increased to .44%; and the zirconium oxide was increased to .36%). With
respect to Experiment
2, it was noted that the increased admixture of Experiment 2 decreased the
initial and final set
time as compared to Experiment l and the control specimen; increased the early
(up to one day)
compressive strength as compared to Experiment 1 and the control specimen; and
increased both
-5-
CA 02237702 1998-OS-14
the exotherm peak and average rate of temperature growth as compared to
Experiment 1 and the
control specimen.
Experiment 3
In Experiment 3, the percentage of the Secar 51 high alumina remained at 50%
of the dry mixture and the sand content of the dry mixture was reduced to 40%.
The admixture
was increased two-fold from Experiment 2, to 10% of the dry mixture, and the
amount of
aluminum oxide, silicon dioxide, zirconium oxide also increased two-fold from
Experiment 2
i.e., the aluminum oxide was increased to 8.4%; the silicon dioxide was
increased to .88%; and
the zirconium oxide was increased to .72%). The increased amount of admixture
included in the
mixture of Experiment 3 further decreased the initial and final set time as
compared to the prior
experiments; increased the early (up to one day) compressive strengths as
compared to the prior
experiments and further increased the exotherm peak and average rate of
temperature growth as
compared to the prior experiments.
Experiment 4
A further control specimen, similar to the earlier control specimen for
Experiments
1 to 3 was conducted with respect to Experiment 4. This further control
specimen substituted
Fondu high alumina cement, sold by Lafarge Calcium Aluminates, Inc., for the
Secar 51 high
alumina cement. In all other respects the control specimen for Experiment 4
was the same as
the control specimen for Experiments 1, 2 and 3. In Experiment 4, the
percentage of the Fondu
high alumina cement remained at 50% of the dry mixture, but the sand content
was reduced
from 50%, as in the control specimen, to 40%. The same admixture as in
Experiment 3, namely
8.4% of aluminum oxide; .88% of silicon oxide and .72% of zirconium oxide, was
added. With
-6-
CA 02237702 1998-OS-14
respect to Experiment 4, both the initial and final set times decreased as
compared to its
corresponding control specimen; the early (up to one day} compressive strength
increased as
compared to the control specimen and both the exotherm peak and average rate
of temperature
growth increased as compared to the control specimen. It was noted that the
compressive
strength at six hours for both Experiment 4 and the control specimen were the
same. A possible
explanation is that the admixture's accelerating effect occurs earlier on the
Fondu HAC than on
the other cements. It may also be the case that the test results fall within
the 10% error of
experiments typical for cementitious materials.
Experiment 5
Another control specimen, similar to the earlier control specimens, was
conducted
with respect to Experiment 5. In this experiment, Lumnite high alumina cement,
sold by Lehigh
Portland Cement Company, was substituted for the Secar 51 high alumina cement
and the Fondu
high alumina cement of the prior control specimen. The control specimen for
Experiment 5 was
the same as the earlier control specimens in all other respects.
In Experiment 5, the percentage of Lumnite high alumina cement remained at 50%
of the dry mixture, but the sand content was reduced from 50%, as in the
control specimen, to
40%. The same admixture as in Experiments 3, 4 and 5, namely 8.4% of aluminum
oxide; .88%
of silicon oxide and .72% of zirconium oxide, was added. With respect to
Experiment 5, both
the initial and final set times decreased as compared to its corresponding
control specimen; the
early (up to one day) compressive strength increased as compared to the
control specimen, and
both the exotherm peak and average rate of temperature growth increased as
compared to the
control specimen.
CA 02237702 1998-OS-14
The following Table 1 includes the quantitative results of Experiments 1 to 5.
TABLE 1
Experiment No. 1 2 3 4 5
Ingredients, %
Properties Control Control Control
-
Secar 51 HAC 50.0 50.0 50.0 50.0- - - -
Fondu HAC - - - - 50.0 50.0- -
Lumnite HAC - - - - - - 50.0 50.0
ASZ admixture) total- 2.5 5.0 10.0- 10.0- 10.0
including
A1203 - 2.1 4.2 8.4 - 8.4 - 8.4
Si02 - 0.22 0.44 0.88- 0.88- 0.88
Zr02 - 0.18 0.36 0.72- 0.72- 0.72
Sand 50.0 47.5 45.0 40.050.0 40.050.0 40.0
Mixing water, %
by weight
of d_nr batch 20%
FOR
ALL
MIXES
Set time, min.
Initial 279 221 166 128 193 145 330 159
Final 336 260 180 150 235 170 375 194
Compressive Strength,
psi
3 hrs. - - 200 3000- _ _ _
4 hrs. - - 1350 5875- 3900- 2850
2S 5 hrs. - 2400 4800 60754100 4750- 4300
6 hrs. 650 5800 6050 61755350 5350- 4550
1 day 8175 8660 8710 90606875 72007100 7375
Exotherm peak
Temperature, F 218 232 240 247 221 241 209 214
Time, min. 462 362 314 223 310 215 469 338
Average rate of
temperature's
rowth F/min. 0.31 0.44 0.54 0.780.48 0.790.29 0.42
Experiment 6
The control specimen for Experiment 6 was similar to the previous control
specimens but substituted portland gray cement, type II, sold by Lehigh
Portland Cement
Company, for the cements of the previous control specimens. The portland gray
cement
comprised 50% of the dry mixture and the sand comprised 50% of the dry
mixture. "Portland
_g_
CA 02237702 1998-OS-14
cement", as used herein, includes those cements normally understood in the art
to be "portland
cements", as described in the designation ASTM C 150.
In Experiment 6, the percentage of the portland cement, type II, remained the
same
at 50% of the dry mixture, but the sand content was reduced to 40% of the dry
mixture. The
admixture comprising 10% of the dry mixture was added. The admixture
formulation was the
same as in Experiments 3, 4 and 5, namely aluminum oxide in the amount of 8.4%
of the total
mixture; silicon dioxide in the amount of .88% of the total mixture; zirconium
oxide in the
amount of .72% of the total mixture. With respect to the results of Experiment
6, both the initial
and final set time decreased compared to the control specimen, the compressive
strength (up to
one day) increased compared to the control specimen, and both the exotherm
peak and average
rate of temperature growth increased compared to the control specimen.
Experiment 7
The control specimen for Experiment 7 was identical to the control specimen
for
Experiment 6, and Experiment 7 was identical to Experiment 6, with the
exception that in both
the control specimen and Experiment 7, portland cement, type III, sold by
Lehigh Portland
Cement Company, replaced the portland cement, type II of Experiment 6. With
respect to the
results of Experiment 7, both the initial and final set time decreased with
respect to the control
specimen, the compressive strength at 5, 6, 7 and 8 hours increased, and both
the exotherm peak
and average rate of temperature growth increased compared to the control
specimen.
-9-
CA 02237702 1998-OS-14
The following Table 2 includes the quantitative results of Experiments 6 and
7.
TABLE 2
Ex riment No.
Ingredients, %
Pro rties Control Control
Portland cement T-II 50.0 50.0 - -
(Lehigh, gray)
Portland cement T-III 50.0 50.0
(L,ehigh, white)
ASZ-admixture, total - 10.0 - 10.0
including:
A1z03 - 8.4 - 8.4
Si02 - 0.88 - 0.88
Zr02 - 0.72 - 0.72
Sand 50.0 40.0 50.0 40.0
Mixing water % by weight
of dry
batch 20%
FOR
ALL
MIXES
Set time, min
~i0~ 205 191 147 120
Final 355 271 202 175
Compressive strength)
psi
5 hrs. - - -
325
6 hrs. - 175 225 625
7 ~.s, 100-125 275 500 1125
8 hrs. 200 425 725 1950
1 da 3500 4000 4550 5750
Ezotherm peak
Temperature, F 113 130 151 164
Time, min. 570 480 438 346
Average rate of temperature's
rowth F/min. 0.07 0.12 0.18 0.28
Experiment 8
The control specimen for Experiment 8 consisted of mixing Secar 51 high
alumina
cement in the amount of 37.5% of the dry mix, portland gray cement, type II,
in the amount of
12.5% of the dry mix and sand in the amount of 50% of the dry mix. In
Experiment 8, the
percentage of the Secar 51 high alumina cement and the portland cement, type
II remained the
-10-
CA 02237702 1998-OS-14
same as the control specimen but the sand content was reduced to 45% and
replaced by the
admixture in the same percentages as Experiment 2, namely aluminum oxide in
the amount of
4.2% of the dry mixture; silicon dioxide in the amount of .44% of the dry
mixture; zirconium
oxide in the amount of .36% of the dry mixture. With respect to the results of
Experiment 8, both
the initial and final set time decreased compared to the control specimen, the
compressive
strength at 2, 3 and 6 hours increased compared to the control specimen and
both the exotherm
peak and average rate of temperature growth increased compared to the control
specimen.
Experiment 9
The control specimen for Experiment 9 was the same as the control specimen for
Experiment 8. In Experiment 9, the percentage of the Secar 51 high alumina
cement and the
portland cement, type II remained the same as the control specimen but the
sand content was
reduced to 40%, and replaced by the admixture comprising aluminum oxide in the
amount of
8.4% of the dry mixture; silicon dioxide in the amount of .88% of the dry
mixture; zirconium
oxide in the amount of .72% of the dry mixture. With respect to the results of
Experiment 9,
both the initial and final set time decreased with respect to the control
specimen, the compressive
strength at 2, 3 and 6 hours increased compared to the control specimen and
both the exotherm
peak and average rate of temperature growth increased compared to the control
specimen.
-11-
CA 02237702 1998-OS-14
The following Table 3 includes the quantitative results of Experiments 8 and
9.
TABLE 3
Experiment
$ Ingredients, %
Properties Control
Secar $1 I-iAC 37.5 37.$ 37.$
Portland T-II 12.$ 12.5 12.5
ASZ-admixture, total
including: - 5.0 10.0
A 1203 - 4.2 8.4
Si02 - 0.44 0.88
ZrOz - 0.36 0.72
1$ Sand $0.0 4$.0 40.0
Mixing water) % by
weight of dry
batch 20k FOR ALL MIXES
Set time) min.
Initial 127 82 71
Final 150 87 81
Compressive strength,
psi
2 hrs. - 950 1650
3 hrs. 800 3900 4000
6 hrs. 4$$0 4675 $150
2$ Exotherm peak
Temperature, F 220 221 223
Time, min. 230 164 171
Average rate of temperature's
growth Flmin 0.64 0.91 0.88
Experiments 10 through 15
- In General
Experiments 10 through 1$ were designed to determine the limits of each of the
compounds used in the admixture. Thus, the aluminum oxide, the silicon
dioxide, and the
zirconium oxide were each tested separately in a cementitious compound
comprising Secar $1
3$ high alumina cement, sand and water. The same control specimen was utilized
for Experiments
10 through 1$. The control specimen comprised a mixture of Secar $1 high
alumina cement with
sand. The dry mixture of the control specimen included equal parts of Secar $1
high alumina
-12-
CA 02237702 1998-OS-14
cement and sand. The water content of the composition comprised 20% of the
weight of the dry
materials.
Experiment 10
In Experiment 10, the percentage of the Secar 51 high alumina cement remained
the same as the control specimen, i.e., 50%; however, the sand content was
reduced to 46.5% and
aluminum oxide in the amount of 3.5% of the total mixture was added. The
amount of
aluminum oxide, 3.5% of the total mixture, was selected on the assumption that
the total
admixture (containing aluminum oxide, silicon dioxide and zirconium oxide)
would comprise 5%
of the total dry mix, and that the aluminum oxide portion of the admixture
would be 70%. Thus,
the aluminum oxide would be 70% of the 5% total dry mix or 3.5%. Neither
silicon dioxide nor
zirconium oxide was added to the mixture. With respect to the results of
Experiment 10, both
the initial and final set time decreased compared to the control specimen, the
early (up to one
day) and seven day compressive strengths increased compared to the control
specimen and both
the exotherm peak and average rate of temperature growth increased compared to
the control
specimen.
Experiment 11
In Experiment 11, the percentage of the Secar 51 high alumina cement remained
the same as the control specimen, i.e., 50%; however, the sand content was
reduced to 40.4% and
aluminum oxide in the amount of 9.6% of the total mixture was added. The
amount of
aluminum oxide, 9.6% of the total mixture, was selected on the assumption that
the total
admixture (containing aluminum oxide, silicon dioxide and zirconium oxide)
would comprise
10% of the total dry mix, and that the aluminum oxide portion of the admixture
would be 96%.
-13-
CA 02237702 1998-OS-14
Thus, the aluminum oxide would be 9.6% of the total dry mix. Neither silicon
dioxide nor
zirconium oxide was added to the mixture. With respect to the results of
Experiment 11, both
the initial and final set time decreased compared to the control specimen and
to Experiment 10,
the early (up to one day) and seven day compressive strengths increased
compared to the control
specimen and both the exotherm peak and average rate of temperature growth
increased
compared to the control specimen and to Experiment 10. The compressive
strength of
Experiment 11 compared to Experiment 10 increased at four and six hours, but
decreased at five,
seven and eight hours and one and seven days.
Experiment 12
In Experiment 12, the percentage of the Secar 51 high alumina cement remained
the same as the control specimen, i.e., 50%; however, the sand content was
reduced to 49.9% and
silicon dioxide in the amount of .1 % of the total mixture was added. The
amount of silicon
dioxide, ,1 % of the total mixture, was selected on the assumption that the
total admixture
(containing aluminum oxide, silicon dioxide and zirconium oxide) would
comprise 5% of the
total dry mix, and that the silicon dioxide portion of the admixture would be
2%. Thus, the
silicon dioxide would be 2% of the 5% total dry mix or .1%. Neither aluminum
oxide nor
zirconium oxide was added to the mixture. With respect to the results of
Experiment 12, both
the initial and final set time decreased compared to the control specimen, but
increased compared
to Experiments 10 and 11, the early {up to one day) and seven day compressive
strengths
increased compared to the control specimen, but decreased compared to
Experiments 10 and 11
and the exotherm peak decreased compared to the control specimen and to
Experiments 10 and
11. The average rate of temperature growth increased compared to the control
specimen, but
-14-
CA 02237702 1998-OS-14
decreased compared to Experiments 10 and 11.
Experiment 13
In Experiment 13, the percentage of the Secar 51 high alumina cement remained
the same as the control specimen, i.e., 50%; however, the sand content was
reduced to 48.5% and
silicon dioxide in the amount of 1.5% of the total mixture was added. The
amount of silicon
dioxide, 1.5% of the total mixture, was selected on the assumption that the
total admixture
(containing aluminum oxide, silicon dioxide and zirconium oxide) would
comprise 10% of the
total dry mix, and that the silicon dioxide portion of the admixture would be
15%. Thus, the
silicon dioxide would be 15% of the 10% total dry mix or 1.5%. Neither
aluminum oxide nor
zirconium oxide was added to the mixture. With respect to the results of
Experiment 13, the
initial set time decreased with respect to the control specimen and with
respect to Experiments
10 through 12. The final set time decreased with respect to the control
specimen and
Experiments 10 and 12 but increased with respect to Experiment 11. The
compressive strength
at four hours increased with respect to Experiments 10 and 11; at five hours
increased with
respect to Experiments 10 and 11; at seven hours increased with respect to the
control specimen
and Experiment 12 but decreased with respect to Experiments 10 and 11; at
eight hours increased
with respect to the control specimen and Experiment 12 but decreased with
respect to Experiment
10 and 11; at one day increased with respect to the control specimen and
Experiment 12 but
decreased with respect to Experiments 10 and 11; and at seven days increased
with respect to the
control specimen and Experiment 12 and decreased with respect to Experiments
10 and 11. The
exotherm peak increased with respect to the control specimen and Experiment 12
and decreased
with respect to Experiments 10 and 11. The average rate of temperature growth
increased
-15-
CA 02237702 1998-OS-14
compared to the control specimen and with respect to Experiments 10 through
12.
Experiment 14
In Experiment 14, the percentage of the Secar 51 high alumina cement remained
the same as the control specimen, i.e., 50%; however, the sand content was
reduced to 49.9% and
zirconium oxide in the amount of .1 % of the total mixture was added. The
amount of zirconium
oxide, .1 % of the total mixture, was selected on the assumption that the
total admixture
(containing aluminum oxide, silicon dioxide and zirconium oxide) would
comprise 5% of the
total dry mix, and that the zirconium oxide portion of the admixture would be
2%. Thus, the
zirconium oxide would be 2% of the 5% total dry mix or .1 %. Neither aluminum
oxide nor
silicon dioxide was added to the mixture. With respect to the results of
Experiment 14, the initial
set time was the same as the control specimen and the final set time was
virtually the same as
the control specimen. The early (up to one day) compressive strengths
increased compared to
the control specimen and Experiment 12 but decreased compared to Experiments
10, 11 and 13.
The seven day compressive strength increased compared to the control specimen
and Experiment
12 but decreased compared to Experiments 10, 11 and 13. The exotherm peak
temperature
increased compared to the control specimen and Experiment 12 and decreased
compared to
Experiments 10, 11 and 13. The average rate of temperature growth increased
with respect to
the control specimen, remained the same with respect to Experiment 12, and
decreased compared
to Experiments 10, 11 and 13.
Experiment 15
In Experiment 15, the percentage of the Secar 51 high alumina cement remained
the same as the control specimen, i.e., 50%; however, the sand content was
reduced to 48.5% and
-16-
CA 02237702 1998-OS-14
zirconium oxide in the amount of 1.5% of the total mixture was added. The
amount of
zirconium oxide, 1.5% of the total mixture, was selected on the assumption
that the total
admixture (containing aluminum oxide, silicon dioxide and zirconium oxide)
would comprise
10% of the total dry mix, and that the zirconium oxide portion of the
admixture would be 15%.
Thus, the zirconium oxide would be 15% of the 10% total dry mix or 1.5%.
Neither aluminum
oxide nor silicon dioxide was added to the mixture. With respect to the
results of Experiment
15, the initial set time was less than the control specimen and Experiment 14,
but greater than
Experiments 10 through 13. The final set time was less than the control
specimen and
Experiment 14, but greater than Experiments 10 through 13. The compressive
strength for seven
and eight hours increased compared to the control specimen and Experiment 14
but decreased
compared to Experiments 10 through 13. The compressive strength for one day
increased
compared to the control specimen and Experiments 12 and 14 but decreased with
respect to
Experiments 10, 11 and 13. The compressive strength for seven days increased
compared to the
control specimen and Experiment 12, was the same as Experiment 14 and
decreased compared
to Experiments 10, 11 and 13. The exotherm peak temperature increased compared
to the control
specimen and Experiments 12 and 14 and decreased compared to Experiments 10,
11 and 13.
The average rate of temperature growth increased with respect to the control
specimen,
Experiments 12 and 14 and decreased compared to Experiments 10, 11 and 13.
The following Table 4 sets forth the results of Experiments 10 through 15.
When
the amount of admixture was lower than that of Experiments 10 through 15, the
accelerating
effect was insignificant or absent. At higher amounts of admixture, other
unacceptable properties
were present (e.~., the material was too stiff to be compacted properly).
-17-
CA 02237702 1998-OS-14
TABLE 4
Experiment No. 10 I1 12 13 14 15
Ingredients,
k
properties Control
HAC (Secar 51) 50.0 50.0 50.0 50.0 50.0 50.0 50.0
A1203 - 3.5 9.6 - - - -
Si02 - - - 0.1 1.5 - -
zro2 - - - - - o.l l.s
Sand 50.0 46.5 40.4 49.9 48.5 49.9 48.5
Mixing water,
%
by wgt. of dry 20%
batch FOR
ALL
MIXES
Set time, minutes
Initial 312 169 144 277 141 312 285
Final 357 192 169 320 173 356 332
Compressive
strength, psi
3 Hrs. - - 350 - _ _ _
4 Hrs. - 825 1950 - 3500 - -
5 Hrs. - 5725 5650 - 6400 - -
2S 6 Hrs. - 7525 7575 - 6600 - -
7 Hrs. 125 8050 7900 1350 7100 175 800
8 Hrs. 1100 8125 8100 5010 7150 1200 4850
1 Day 6325 8475 8250 6800 8000 6850 7050
7 Days 8350 10650 105508450 9800 8550 8550
Exotherm peak
temperature, 218 241 243 213 232 222 226
F
time, minutes 513 339 371 463 293 486 450
Average rate
of
temperature's
growth, F/min. 0.29 0.50 0.47 0.31 0.55 0.31 0.35
Experiments lb and 17
- In General
Experiments 16 and 17 were designed to determine the effect of certain
plasticizing agents on the cementitious composition. The plasticizing agents
were Lomar DF,
which includes a defoamer, and is sold by Henkel Corp., and MCG SC9, which is
sold by
Morristown Chemical Group. The plasticizing agents may include naphthalene
sulfonate based
-18-
CA 02237702 1998-OS-14
compounds, melamine sulfonate based compounds and ligmosulphonate based
compounds.
Experiment 16
The control specimen comprised a mixture of Secar 51 high alumina cement with
sand. The dry mixture of the control specimen included 50% of Secar 51 high
alumina cement,
49.9% of sand and 0.1% of MCG-SC9. The water content of the composition
comprised 1b.5%
of the weight of the dry materials.
In Experiment 16, the percentage of the Secar 51 high alumina cement remained
the
same as the control specimen, i.e. 50%; however, the sand content was reduced
to 44.9% and
MCG-SC9 in the amount of .1 % of the total mixture was added. The amount of
water was
increased to 18.75% of the weight of the dry material. Admixture in the amount
of 4.15% of
aluminum oxide, .425% of silicon dioxide and .425% of zirconium oxide was
included in the
mixture. With respect to the results of Experiment 16, the final set time was
reduced compared
to the control specimen (because of the previously noted retardation effect of
the plasticizing
agent, the initial set time was not tested, nor was compressive strength at
six or eight hours).
The one day and seven day compressive strengths increased compared to the
control specimen
and both the exotherm peak and average rate of temperature growth increased
compared to the
control specimen.
Ex~,eriment 17
The control specimen comprised a mixture of portland cement, type II, sold by
Lehigh Portland Cement Company, with sand. The dry mixture of the control
specimen included
50% of such cement, 49.8% of sand and .2% of Lomar DF. The water content of
the
composition comprised 18.25% of the weight of the dry materials.
-19-
CA 02237702 1998-OS-14
In Experiment 17, the percentage of the Lehigh type II cement remained the
same
as the control specimen, i.e., 50%; however, the sand content was reduced to
44.8% and Lomar
DF in the amount of .2% of the total mixture was added. Admixture in the
amount of 4.15% of
aluminum oxide, .425% of silicon dioxide and .425% of zirconium oxide was
included in the
mixture. With respect to the results of Experiment 17, both the initial and
final set times were
reduced compared to the control specimen. The eight hours, one day and seven
day compressive
strengths increased compared to the control specimen and both the exotherm
peak and average
rate of temperature growth increased compared to the control specimen. The
results of
Experiments 16 and 17 are shown in Table 5.
-20-
CA 02237702 1998-OS-14
TABLE 5
Experiment No. 16 17
Ingredient, °lo
$ Properties Control Control
HAC (Secar 51) 50.0 50.0
Portland (Lehigh - - 50.0 50.0
T-In
ASZ - admixture
total - 5.0 - 5.0
including A1z03 - 4.15 - 4.15
Si02 - 0.425 - 0.425
Zr02 - 0.425 - 0.425
water-reducers
1S Lomar DF - - 0.2 0.2
MCG-SC9 0.1 0.1 - -
Sand 49.9 44.9 49.8 44.8
Mixing water 16.5 18.75 18.25 18.75
Set time
Initial - - 247 204
Final 887 819 367 340
Compressive strength,
psi
6 Hrs. - - - -
g mss. - - 250 600
1 Day 3000 10800 4500 4925
7 Davs 6925 12700 7100 7725
Exotherm peak
Temperature F 128 153 120 131
Time, minutes 3175 1495 520 417
Avg. rate of
temperature's
growth) F/minutes 0.02 0.06 0.09 0.14
Experiments 18 and 19
- In General
Experiments 18 and 19 were designed to determine the effect on the
cementitious
composition of the presence of certain air releasing and/or gas generating
agents. The air
releasing agent was fluidized coke sold by Five Star Products, Inc. under the
trademark "PLA"
(hereinafter "PLA") and the gas generating agent was azodicarbonamide sold by
Uniroyal
Chemical under the trademark "AZ-130" (hereinafter "AZ-130"). The water
content of
-21-
CA 02237702 1998-OS-14
150P14CA
Experiments 18 and 19, and their respective control specimen was 20% of the
weight of the dry
mixture.
Experiment 18
The control specimen comprised a mixture of Secar 51 high alumina cement with
sand. The dry mixture of the control specimen included 50% of Secar 51 high
alumina cement,
47% sand and 3% of PLA.
In Experiment 18, the percentage of the Secar 51 high alumina cement remained
the
same as the control specimen, i.e., 50%; however, the sand content was reduced
to 42% and PLA
in the amount of 3% of the total mixture was included. Admixture in the amount
of 4.15% of
aluminum oxide, .425% of silicon dioxide and .425% of zirconium oxide was
included in the
mixture. With respect to the results of Experiment 18, the initial and final
set times were
reduced compared to the control specimen. In the plastic state, the volume
change of the
composition was less than the volume change of the control specimen. The seven
hours, eight
hour and one day compressive strengths increased compared to the control
specimen and both
the exotherm peak and average rate of temperature growth increased compared to
the control
specimen.
Experiment 19
The control specimen comprised a mixture of Secar 51 high alumina cement with
sand. The dry mixture of the control specimen included 50% of Secar 51 high
alumina cement
and 49.99% sand and .Ol % of AZ-130.
In Experiment 19, the percentage of the Secar 51 high alumina cement remained
the
same as the control specimen, i.e., 50%; however, the sand content was reduced
to 44.99% and
-22-
CA 02237702 1998-OS-14
AZ-130 in the amount of .O1 % of the total mixture was included. Admixture in
the amount of
4.15% of aluminum oxide, .425% of silicon dioxide and .425% of zirconium oxide
was included
in the mixture. With respect to the results of Experiment 19, the initial and
final set times was
reduced compared to the control specimen. In the plastic state, the volume
change of the
composition was less than the volume change of the control specimen. The one
day compressive
strengths increased compared to the control specimen, and both the exotherm
peak and the
average rate of temperature growth increased compared to the control specimen.
The following
Table 6 sets forth the results of Experiments 18 and 19.
TABLE 6
Experiment No. 18 19
Ingredient, %
Properties Control Control
HAC (Secar 51) 50.0 50.0 50.0 50.0
ASZ - admixture
total - 5.0 - 5.0
including A1203 - 4.15 - 4.15
Si02 - 0.425 - 0.425
Zr02 - 0.425 - 0.425
PLA 3.0 3.0 - -
AZ-130 - - 0.01 0.01
Sand 47.0 42.0 49.99 44.99
2S Mixing Water, % 20% FOR ALL MIXES
Set time, minutes
Initial 326 197 363 260
Final 369 220 422 275
Volume changes in plastic+1.78 +1.65 +0.03 +0.025
state, %
Compressive strength)
psi
4 Hrs. - 425 - _
5 Hrs. - 4100 - 500
6 Hrs. - 5400 - 2250
3S 7 Hrs. 5000 6225 - 5200
8 Hrs. 5200 6625 5300 -
1 Day 6250 7875 6600 8075
Exotherm peak:
Temperature, F 225 246 230 248
Time, minutes 465 368 480 385
Avg. rate of temperature's
growth, F/minutes 0.33 0.47 0.33 0.46
-23-
CA 02237702 1998-OS-14
Experiment 20
Experiment 20 was designed to determine the effect on the cementitious
composition
of an air-entraining agent, vinsol resin (hereinafter "NVX").
The control specimen comprised a mixture of Secar 51 high alumina cement with
sand. The dry mixture of the control specimen included 50% of Secar high
alumina cement and
49.99% sand and .01 % of NVX. The water content of Experiment 20 was 20% of
the weight
of the dry mixture.
In Experiment 20, the percentage of the Secar 51 high alumina cement remained
the
same as the control specimen, i.e., 50%; however, the sand content was reduced
to 44.99% and
NVX in the amount of .01 % of the total mixture was included. Admixture in the
amount of
4.15% of aluminum oxide, .425% of silicon dioxide and .425% of zirconium oxide
was included
in the mixture. With respect to the results of Experiment 20, the initial and
final set times were
reduced compared to the control specimen. The seven hours, eight hours and one
day
compressive strengths increased compared to the control specimen, the exotherm
peak remained
the same as the control specimen and the average rate of temperature growth
increased compared
to the control specimen. The results of Experiment 20 are shown in Table 7.
-24-
CA 02237702 1998-OS-14
TABLE 7
Experiment No.
Ingredients, %
properties Control
I-IAC (Secar 51) 50.0 50.0
ASZ-admixture
total - 5.0
including A1203 - 4.15
Si02 - 0.425
ZROZ - 0.425
0.01 0.01
Sand 49.99 44.99
Mixing Water, % 20.0
Set time, minutes
~id~ 290 211
Final 345 241
Compressive strength,
psi
4 Hrs. - -
5 Hrs. - 1975
6 Hrs. 300 3650
7 Hrs. 2900 5025
g ~.s_ 4350 5275
1 Day 5975 6800
Exotherm peak
Temperature, F 222 222
Time, minutes 636 443
Avg. rate of temperature's
growth, F/minutes 0.24 0.33
Experiment 21
Experiment 21 was designed to determine the effect on the cementitious
composition of a corrosion inhibitor NaN02.
The control specimen comprised a mixture of portland cement, type II with
sand.
The dry mixture of the control specimen included 50% of such cement and
49.0°lo sand and 1 °lo
of NaN02. The water content of Experiment 20 was 20% of the weight of the dry
mixture.
-25-
CA 02237702 1998-OS-14
In Experiment 21, the percentage of the portland cement, type II remained the
same as the control specimen, i.e., 50%; however, the sand content was reduced
to 44% and
NaNOz in the amount of 1 % of the total mixture was included. Admixture in the
amount of
4.15% of aluminum oxide, .425% of silicon dioxide and .425% of zirconium oxide
was included
in the mixture. With respect to the results of Experiment 21, the initial and
final set times were
reduced compared to the control specimen. The six hours, seven hours, eight
hours and one day
compressive strengths increased compared to the control specimen, and both the
exotherm peak
and the average rate of temperature growth increased compared to the control
specimen. The
results of Experiment 21 are shown in Table 8.
TABLE 8
Experiment No. 21
Ingredients, °k
Properties Control
Portland) T-II 50.0 50.0
ASZ-admixture
total - 5.0
including A1203 - 4.15
Si02 - 0.425
2~ Zr02 - 0.425
NaN02 1.0 1.0
Sand 49.0 44.0
Mixing water, % 20.0
Set time, minutes
Initial 228 224
Final 324 303
Compressive strength) psi
6 Hrs. 125 125
7 Hrs. 250 275
8 Hrs. 4~ S~
1 Dav 3350 4000
Exotherm peak
Temperature, F 118 122
Time, minutes 533 503
Avg. rate of temperature's
growth, F/minutes 0.08 0.1
-26-
CA 02237702 1998-OS-14
Experiment 22
Experiment 22 was designed to determine the effect on the cementitious
composition of the presence of a mineral admixture, class C fly ash.
The control specimen comprised a mixture of portland cement, type II with
sand.
The dry mixture of the control specimen included 40% of cement, 50% of sand
and 10% of fly
ash Class C. The water content of the control specimen and Experiment 22
comprised 20% of
the weight of the dry materials.
In Experiment 22, the percentage of the portland cement, type II remained the
same as the control specimen, i.e., 40%; however, the sand content was reduced
to 40% and fly
ash Class C in the amount of 10% of the total mixture was added. Admixture in
the amount of
8.3% of aluminum oxide, .85% of silicon dioxide and .85% of zirconium oxide
was included in
the mixture. With respect to the results of Experiment 22, the initial and
final set times were
reduced compared to the control specimen. The eight hour, twelve hour and one
day compressive
strengths increased compared to the control specimen and both the exotherm
peak and average
rate of temperature growth increased compared to the control specimen.
The results of Experiment are shown in Table 9.
-27-
CA 02237702 1998-OS-14
TABLE 9
Experiment No. 22
Ingredients, ~
Properties Control
Portland T-II 40.0 40.0
Fly ash Class C 10.0 10.0
ASZ-admixture
total - 10.0
including A1203 - 8.3
Si02 - 0.85
Zr02 - 0.85
Sand 50.0 40.0
1S Mixing water, % 20.0
Set time, minutes
Initial 334 235
Final 432 325
Compressive strength,
psi
6 Hrs. -
8 Hrs. 50 175
12 Hrs. 500 1000
1 Day 2325 2850
Exotherm peak
Temperature) F 108 109
Time, minutes 720 588
Avg, rate of temperature
growth, F/minutes 0.05 0.06
While the invention disclosed herein is calculated to provide an improved
admixture for a cementitious system over those described in the prior art, it
will be appreciated
that alternate embodiments may be devised by those skilled in the art. It is
therefore intended
that the appended claims cover all modifications or embodiments as fall within
the true spirit and
scope of the present invention.
-28-
