METHODE DE PRODUCTION DE MORTIER ENTREPOSABE

METHOD FOR PRODUCING A STORABLE MORTAR

Abrégé anglais

METHOD FOR PRODUCING A STORABLE MORTAR
ABSTRACT OF THE DISCLOSURE
A method for controlling the setting of a
cementitious composition of matter, the present inven-
tion allows mixing of a mortar and retention thereof
for a prolonged period of time before use, the mortar
setting at least as rapidly as normally when applied
to brick, block, or the like during the period of
retention. The method involves the addition of an ef-
fective amount of saccharide polymers having a size of
from three glucose units to on the order of 25 glucose
units to a cementitious mixture, the additive optionally
including air entrainment agents and similar agents
such as have been previously used in the formulation
of mortars. The method further involves entraining
air in the mortar mixture to a particular degree which
allows control of the setting rate of the mortar mixture
when evaporation from the mixture is controlled. The
invention further provides cementitious compositions of
matter capable of being stored in a plastic state for
a prolonged period of time, the composition setting at
least as rapidly as normally when applied to brick,
block, or the like.

Revendications

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A method for controlling the initiation of
hydraulic hydration of hydraulic mortar mixtures formed
of cementitious material, aggregate and water to allow
prolongation of the setting times of such mixtures while
retaining workability prior to setting and retaining normal
strength characteristics subsequent to setting and to
cause the setting rate on initiation of hydraulic hydra-
tion to be at least as rapid as that of hydraulic mortar
mixtures which have not undergone suspension of hydraulic
hydration, comprising the steps of:
mixing with the hydraulic mortar mixture an
effective amount of an additive comprised of saccharide
polymers, each said saccharide polymer being composed
of glucose units and having a size of from 3 glucose
units to on the order of 25 glucose units;
storing the resulting admixture of additive
and hydraulic mortar mixture under sealed conditions
at ambient atmospheric pressure for a period of time
exceeding the normal setting time of the hydraulic
mortar mixture to minimize moisture evaporation from
the admixture; and
removing the admixture from the sealed con-
ditions at the time of intended use of the admixture
to allow initiation of setting to proceed.

2. The method of claim l and further comprising
the step of:
applying the admixture of additive and hydraulic
mortar mixture to brick, block and the like after removal
of the admixture from the sealed conditions to facilitate
setting of the admixture.
3. The method of claim 1 wherein the step of
mixing of the additive and hydraulic mortar mixture further
comprises entraining air in the mixture in a range by
volume of between 12 and 35% of the admixture.
4. The method of claim 1 and further comprising
the step of:
entraining air in the admixture in a range by
volume of between 20 and 30% of the admixture prior to
storing of the admixture.
5. The method of claim 1 wherein the additive
is mixed with the hydraulic mortar mixture in a weight
ratio between 2 and 20 ounces of the additive for each
100 pounds of cementitious material.
6. The method of claim 3 wherein the range
is between 25 and 30%.
21

Description

1148176
The invention relates to cementitious composi-
tions which set on admixture with water and particularly
to a method for controlling the temporal interval between
mixture of the compositions with water and the setting
thereof.
Mortar compositions have long been used for
construction purposes, those mortar compositions presently
in use usually containing Portland cement and aggregates
which harden on addition of water. Portland cement
compositions are hydraulic in nature, that is, such
compositions are capable of hardening under water or
when not in the presence of air. On addition of water
to hydraulic cement compositions, a process known as
"hydraulic hydration" occurs, the composition hardening
as a result of this hydration. According to present
practices, additive compositions are known which are
primarily used to strengthen hydraulic cement composi-
tions. Additive compositions are also known which
retard or accelerate the setting of hydraulic cement
compositions. However, retarding compositions have
not been greatly effective due to the unpredictability
of their behavior, certain cement compositions being
completely inhibited from hydration when such additive
compositions are utilized. It has not been possible,
therefore, according to prior art practices to control-
lably retard the setting of mortar compositions, parti-
cularly hydraulic cement compositions, in a manner which
allows holding of mortar in a plastic, workable state
for any extended period of time and still retain the
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8~76
capability of immediate setting of the mortar when the
mortar is actually used at some time during this holding
period.
Additives previously used in the formulation of
mortar include agents which act to strengthen the mortar,
entrain air in the mortar, plasticize the mortar, color
the mortar, and vary setting times of mortars. As
disclosed by Kelly et al in U. S. Patent No. 3,432,317,
saccharide polymers inter alia are added to cementitious
materials in order to strengthen the hardened mortar. The
saccharide polymers so disclosed provide a strengthening
function without retarding the setting rate of the mortar
according to the invention disclosed by Kelly et al. It
is noted in the aforesaid patent that sugars, such as the
glucosaccharides of the patent, are retarders of cement
hydration and are unpredictable in use. Therefore, the
teachings of Kelly et al do not provide an additive for
or a method for controlling the setting of a cementitious
material, particularly a hydraulic cement, which allows
a hydraulic mortar to be formed and held for an extended
period of time.
In U. S. Patent No. 3,432,316, Kelly et al
disclose the addition of extracts or portions of the tobacco
plant to hydraulic cement in order to increase the strength
of the concrete formed thereby and to cause a degree of
retardation of hardening of the cement. Kelly et al do
not disclose a method for maintaining a hydraulic mortar
mixture in a plastic, workable condition for an extended
period of time. Kelly et al further do not disclose a
method for utilizing a mortar mixture which has been or

1~8~76
can be maintained in a plastic, workable condition for
an extended period of ti~me and which can be used at any
time during this extended period of time with the mortar
mixture setting up as rapidly or more rapidly than normally
on application of said mortar mixture to brick, block,
or the like.
The present invention particularly provides a
method for suspending the hydraulic hydration of hydraulic
cementitious mixtures, such as of Portland cement and
the aggregate and additives normally mixed therewith.
The present method comprises the admixture with cemen-
titious mixtures, particularly hydraulic cementitious
mixtures, of an additive comprised of glucosaccharide
polymers preferably having a size of three glucose units
to approximately 25 glucose units. The hydraulic cemen-
titious mixtures thus formed, which mixtures may contain
pozzolanic materials, such as fly ash, coloring agents, air
entraining agents, and the like, can be stored in sealed
containers and be thus held in a plastic, workable condition
for a period of approximately 72 hours. The invention
further teaches that this stored mixture can be used at
any time during the storage period with the result that
the mixture sets as rapidly or more rapidly than normally
when applied to block~ brick and the like. Therefore,
the invention enables a user of mortar to purchase or make
up at one time a sufficient amount of mortar needed for a
time period of up to three full days. The mortar needed
for most jobs can thus be purchased, delivered, and/or
made up at one time, thereby introducing desirable econo-
mies into the marketing and use situations surrounding

~81~6
the utilization of mortar. Further, mortar sufficientfor use over an extended time period can be made up at a
central facility and delivered to job sites in quantities
sufficient for two to three days usage, the quality of
mortar made under such circumstances being controlled
more readily than is possible for mortar made up at a
job site.
The present invention, therefore, makes possible
the single delivery of quantities of pre-mixed mortar
formulated under relatively precise quality control
conditions, which quantities are sufficient for multiple
day usage and which can be used at any time during a
storage period of up to three days. The hydraulic hydration
action of the stored mortar is suspended according to
the invention until such time as the mortar is actually
used and applied to brick, block, and the like, in a
normal manner. When used, the mortar immediately begins
normal setting and strength development, some mortars
hardening to a given strength even more quickly than when
used normally. Thus, a user of the mortar according to
the invention can maintain a single delivery of mortar in
a usable plastic state for an extended period of time
and retain normal workability,consistency, setting rate,
and strength development.
Application of mortar formulated according to
the invention to brick, block, and the like, initiates
hydraulic hydration of the mortar due to absorption of
moisture from the mortar not only by the atmosphere but
also by the brick and block itself. Therefore, the pre-
sent invention teaches the retardation of setting of mortar

~148~L76
for an extended period of time which is at least of theorder of 72 hours under sealed conditions whereby moisture
evaporation from the mortar is minimized, the mortar
remaining in a workable, plastic condition. Further, the
invention teaches the immediate setting and attainment
of normal strength when applied to brick, block, and the
like, on use of the mortar at any time during the storage
period.
The present invention further teaches the en-
trainment of air in a mortar having the storage and use
characteristics referred to herein, air being entrained
in the mortar in percentages greater than normal in order
to assist in the attainment of the aforesaid storage and
use characteristics of the mortar. Air entrained in the
mortars according to the invention is within a percentage
range by volume of the mortar of 12% to 35%, the higher
percentage amounts being particularly suited to attain-
ment of the storage and use characteristics according
to the invention.
It is therefore an object of the present
invention to provide a method for controlling the setting
of a cementitious composition of matter, the present method
particularly allowing the mixture of a mortar and re-
tention thereof for a prolonged period of time before use,
the mortar setting at least as rpaidly as normally when
applied to brick, block, or the like, at any time during
the period of retention.
It is another object of the invention to provide
a method comprising the addition of an effective amount

~ 8~76
of saccharide polymers having a size of from three glucose
units to on the order of 25 glucose units to a hydraulic
cementitious mixture and subsequently storing the mortar,
the mortar then being capable of usage at any time
during a prolonged storage period without loss of
desirable setting and strength development characteris-
tics.
It is a further object of the invention to provide
a method for suspending the hydraulic hydration of hydraulic
cementitious mixtures, such as of Portland cement and
the aggregates and additives normally admixed therewith,
the present method comprising admixture with the mortar
of glucosaccharide polymers, entrainment of relatively
large quantities by volume of air in the mortar, and the
prevention of moisture evaporation from the mortar until
the time of actual use, such as by storage of the mortar
in sealed containers.
Other objects and advantages of the invention
will become more readily apparent in light of the fol-
lowing detailed description of the preferred embodimentsof the invention.
In a preferred practice of the present inven-
tion, a mortar which can be stored and maintained in
a plastic workable state for an extended period of time
is mixed at a central location for delivery to job sites.
The mortar formulated according to the invention is
containerized at the mixing location, the mortar being
maintained in sealed containers for storage at the job
sites. In this fashion, quality control of the mortar
produced according to the invention is improved due to
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the fact that the mortar is mixed at a central location
rather than on the individual job sites. The teachings of
the present invention allow such mixing at a central lo-
cation since the mortar according to the invention can
be stored for a period of 72 hours or more without loss
of workability. Therefore, relatively lower quality small
batches of mortar need not be continually mixed at job
sites so that only enough mortar necessary for use over
a short future time period is provided. According to the
present invention, quantities of Mortar sufficient for use
over a two to tllree day time period can be centrally mixed
with control of the quality thereof and then stored at
job sites without loss of workability. Due to mixing of
the mortar at a central location, there is no need to pro-
vide water at job sites or to provide sand stockpiles
and quantities of baggedcementitious materials which
need to be covered and protected against the elements.
The present invention further allows the use of pozzo-
lanic materials, particularly fly ash, which allows an
increase in the strength of the mortar.
The present method particularly comprises the
admixture with a hydraulic mortar mix of cement, aggre-
gate, and sufficient water to effect hydraulic setting
of the cement mix with an additive comprising saccharide
polymers having a size of from three glucose units to on
the order of 25 glucose units. Saccharide polymers useful
in the practice of the present invention are described
in U. S. Patent No. 3,432,317. ~hen using
additives according to the aforesaid patent, it
~,. _ :, j
~, .,

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is to be understood that lesser amounts of glucosaccharides
are normally used when more rapid hardening of the cemen-
titious mixture is desired, more glucosaccharides being used
when retardation is desired. Similarly, lesser amounts
of chlorides or other desiccants are to be used when
retardation of the setting of a cementitious mixture is
desired,a greater amount of said substances being used when
it is desired for the mixture to harden more rapidly.
The present invention particularly contemplates
the usage of additive mixtures disclosed in the aforesaid
patent which include as the primary constituent the gluco-
saccharides so disclosed, the glucosaccharides being par-
ticularly present in the mixtures according to the invention
in quantities greater than those quantities disclosed in
the aforesaid patent.
The present method provides a hydraulic mortar
mixture which can be used at any time during the prolonged
storage period as aforesaid, the mortar immediately setting
and developing usual strength characteristics as soon as
the mortar is applied to brick, block, and other similar
building materials. Accordingly, the use of the present
invention does not result in a delay in setting time or
strength development as is the case with prior retardation
compositions and methods. It is a teaching of the inven-
tion that the normal hydraulic hydration process which
occurs in the otherwise retarded settability of the
present mortar mixtures is accelerated by absorption
of moisture by the building materials to which the mortar
is applied. Accordingly, the mortar immediately begins
setting at least as rapidly as it normally would if the

~14t3~76
mortar had not been formulated with an additive according
to the invention which allows storage of the mortar for a
prolonged period of time. Further, the normal strength
development of the mortar is not affected by the process
of the invention.
As can be appreciated by the disclosure provided
herein, the present invention provides a method of sus-
pending the hydraulic hydration action of mortar mixtures,
the invention allowing either immediate use of the mortar
or use after a prolonged storage period. While the gluco-
saccharides essentially disclosed in the aforesaid patent
are utilized as the additive according to the present
method which acts to accomplish the unexpected results and
advantages of the present invention, it is to be noted
that there is no teaching in the aforesaid patent which
would lead one of ordinary skill in the art to the conclusion
that such additives would be useful to produce the results
and advantages provided by the present invention, there
particularly being no indication in the aforesaid patent
that the prevention of moisture evaporation from mortars
formulated according to the invention would prevent
setting of such mortars for prolonged periods of time.
The methods of the present invention particularly
relate to formulation of mortars which contain as one
constituent thereof hydraulic cements such as Portland
cement, such cements typically being comprised of finely
divided gray powder composed of lime, alumina, silica and
iron oxide as tetracalcium aluminoferrate, tricalcium
aluminate, tricalcium silicate, and dicalcium silicate.
_g_

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Such cements typically also comprise small amounts of
magnesia, sodium, potassium and sulphur. Portland cement
when provided with water for hydration will harden under
water, air not being required for hardening of such mix-
tures. Sand and other substantially inert aggregate
material is usually added to Portland cement as a diluent.
Other additives, such as coloring additives, air entrain-
ment agents, and the like can also be added to Portland
cement in a known fashion and can be used in the practice
of the present invention.
It is particularly to be noted that air entrain-
ment agents can be added to the mortar compositions formed
according to the present methods, such air entrainment
agents being well-known in the art. Exemplary of such
agents is the proprietary material known commercially as
Vinsol Kesin, a product of the Hercules Powder Company,
which is a hard, brittle, dark-colored, thermoplastic resin
derived from pine wood, and containing phenol, aldehyde,
and ether groups. This product is supplied in lump, flake,
and pulverized forms, and as a stable emulsion. Other
air entrainment agents are commercially available and are
well-known in the art. Such air entrainment agents can
be used according to the invention to increase the volu-
metric quantity of air entrained within mortars according
to the present invention when the volumetric quantities of
air entrained within the mixtures are to be increased over
the quantities provided by the admixture into the mortar
of the glucosaccharide additives according to the invention.
While mortars useful according to the invention can be
formulated with a quantity of entrained air as low as 12%
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~48176
of the volume of the mortar, it is preferred that the
quantity of air entrained be equivalent to 20 to 30%
of the volume of the mortars. This greatly increased
quantity of air entrained according to the present inven-
tion facilitates use of the mortars according to the
invention to provide the results and advantages referred
to herein. The volumetric quantity of entrained air
according to the invention can be greater than 30%, a
quantity of 40% being within a desired range. When
the volumetric quantity of entrained air in mortars
formulated according to the present invention is to
be increased over and above that amount of air entrained
by admixture of the glucosaccharide additives, commer-
cially available air entrainment agents may be used in
a known fashion to increase the volumetric quantity of
air entrained in the mortar.
The present invention particularly provides
for the use of pozzolanic materials, particularly fly
ash, in the mortar mixtures formulated according to the
invention. Generally, pozzolanic materials are pul-
verulant siliceous or siliceous and aluminous substances
which react chemically with lime and moisture at ordinary
temperature to form a cementitious material. According
to the present invention, pozzolanic materials, particular-
ly fly ash which comprises the noncombustible ash carried
out of a bed of solid fuel by draft, are utilized with
hydraulic cement, such as Portland cement, and without
the addition of slaked lime to form a mortar mixture
of substantial strength and which has the storage and
setting characteristics referred to herein. Accordingly,

~8~76
while the Portland cements useful according to the
invention may contain lime which is not hydrated, hydrated
lime is not added to the mortar mixtures according to the
invention, it being thereby possible to eliminate the
whiting effervescence on the surface of mortars which
typically contain hydrated lime. Further, it is known
that concrete/mortar aggregates in certain geographical
locations contain a water soluble calcium content which
is present in sufficient quantity which, when combined
with Portland cement and water, accelerates the hydraulic
hydration action thereof to a point that such aggregates
are undesirable for use. By utilizing the glucosaccharide
additives according to the teachings of the present inven-
tion in percentages at the upper portion of the desired
range according to the present invention, such adverse
conditions can be controlled and such aggregates can then
be used without the undesirable characteristics previously
encountered in their use.
Accordingly, it is to be seen that the different
characteristics of Portland cements and the different
characteristics of aggregates which occur in different
geographic locations can be overcome through the practice
of the present invention such that adverse setting times
do not occur under such conditions. By varying the
quantity of additives according to the present invention,
these differing characteristics of Portland cements and
aggregates can be controlled in order to produce a desired
settability of mortars formed from such materials. In
particular, these materials having different characteristics
can be controllably suspended in a mortar mix in a desired

~148176
plastic state of workability for periods of at least
72 hours, the mortar being capable of use at any time
during this prolonged period as aforesaid.
Mortar formed according to the present invention
has as the primary ingredient thereof standard cementitious
materials which conform to certain American Society
Testing Material Standards. In particular, the fol-
lowing materials are of particular use:
(1) Portland cement of Types I, II and III
ASTM Designation C-150;
(2) Portland blast furnace slag cement of
Types IS, IS(MS), IS-A and IS-A(MS), ASTM Designation
C-595 for blended hydraulic cement;
(3) Fly ash and raw or calcined natural
pozzolans according to ASTM Designation C-618; and
(4) Masonry cement type II, ASTM Designation
C-91 for masonry cement.
Aggregates useful in the formation of standard
mortars, ASTM Designation C-144, are also useful according
to the present invention. Water which is used in the
formation of the present mortars should be clean and
potable. Methods used for measuring materials useful
in mortars according to the invention should be such that
the specified proportions of the mortar materials can be
controlled and accurately maintained according to ASTM
Designation C-94. It is to be further understood that
mortars according to the present invention are mixed
and delivered to a job site in conformation to the
requirements of the National Ready-Mix Concrete Association.
The mortars formulated according to the invention are
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particularly to be stored in containers of suitable size
and which are capable of being sealed from ambient until
the mortar is used. Mortar proportioning in the practice
of the present invention should also conform with ASTM
Designations C-476, particularly Table I thereof. The
ASTM Designations referred to herein are further incor-
porated hereinto by reference.
The additive particularly useful according to
the present invention comprises saccharide polymers which
are described in U. S. Patent No. 3,432,317, each said
saccharide polymer being composed of glucose units and
having a size of from three glucose units to on the order
of 25 glucose units. It is preferred that a larger pro-
portion of the saccharide polymers have from three glucose
units to on the order of 10 glucose units in the polymer
structure. The amount of the glucosaccharide polymeric
additives mixed with the cementitious materials according
to the present invention to produce a mortar having the
characteristics described herein typically varies between
two and twenty ounces of the additive for each 100 pounds
of cement employed in the mortar. A range of six to
eight ounces of the additive is preferred for most cement
materials, particularly most Portland cement materials.
Utilization of the glucosaccharide additives according
to the invention enables sufficient air to be entrained
in the mortar mixture to facilitate development of the
characteristics particular to the invention, that is, the
production of a desired retardation with maintenance of
a desired workability of the mortar and the accomplishment
of an immediate setting and strength development of the
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mortar on application thereof to brick, block, stucco,
gunite, and other building materials. In order to produce
an air entrainment factor in the mortar mixtures accor-
ding to the invention, air entrainment agents of known
composition can be added to the mortar mixtures in order
to increase the air entrainment factor to between 12 and 35%,
particularly 18 to 27% of the volume of the mortar mixture.
Water evaporation within the present mortar mixtures
can be retarded in a manner additional to storage of the
mortar within said sealed containers, particularly by
the addition of resins, such as methyl cellulose and
hydroxyethyl cellulose.
A mortar formulated according to the present
invention using 6.6 ounces of the glucosaccharide additive
material as described hereinabove per 100 pounds of Port-
land cement produced case test samples having the fol-
lowing strength given in pounds per square inch, the
mortar from which the test samples were cast containing
.0768 units of absolute volume of Portland cement and
20 0.0523 units of absolute volume of fly ash mixed with
- masonry sand and water:
Test Results Reported in Pounds Per Square Inch
Time In
Suspension 7-Day Results 21-Day Results 28-Day Results
24 hours 2570 psi 3760 psi 3920 psi
48 hours 2705 psi 3860 psi 3910 psi
72 hours 2810 psi 3845 psi 3830 psi
Examples of particular mortar mixtures according
to the present invention are provided hereinafter, it being
understood that such examples are exemplary only and are
not limiting of the invention as described herein. In
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each of the following examples, each unit of cement
indicated as "Sacks" is a 94 pound unit. The saccharide
additive employed in the examples essentially comprises
glucosaccharide polymers as described hereinabove.
EXAMPLE I
-
1 cu. yd Batch wt. Abs. vol.
Cement 6.13 Sacks 576 pounds2.942
Ash 192 " 1.338
Water 39.1 Gal. 326 " 5.227
10 Sand 1826 " 11`.089
Saccharide additive to obtain 7 ounces per 100# 6.404
23.7~ air entrainment of cementitious ~Entrained
materialsair)
2900 pounds 11.089 cu.ft.
107.4 pounds per cubic foot
Average 7-day test results 2050 psi
Average 28-day test results 3365 psi
EXA~lPLE II
1 cu. yd. Batch wt. Abs. vol.
20 Cement 5.46 Sacks 513 pounds2.621
Ash 205 " 1.259
Water 34.7 Gal. 289 " 4.639
Sand 1948 " 11.551
Saccharide additive to 7.2 ounces per 100# 6.930
obtain 27.5~ air of cementitious(Entrained
entrainment materials air)
2955 pounds27.000cu.ft.
109.4 pounds per cubic foot
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Average 7-day test results 1860 psi
Average 28-day test results 2830 psi
EXAMPLE III
1 cu. yd. Batch wt. Abs. vol.
-
Cement 5.05 Sacks 475 pounds 2.424
Ash 178 " 1.240
Water 41.4 Gal. 345 " 5.535
Sand 1997 "12.262
Saccharide additive5.8 ounces per 100# 5.539
to obtain 20.5%of cementitious (entrained
air entrainment materials air)
2995 pounds27.000 cu.ft.
110.9 pounds per cubic foot
Average 7-day test results 1685 psi
Average 28-day test results 2715 psi
EXAMPLE IV
1 cu. yd. Batch wt. Abs. vol.
Cement 4.84 Sacks 455 pounds 2.323
Ash 182 " 1.268
Water 43.2 Gal. 360 " 5.775
Sand 1844 "11.322
Saccharide additive6.9 ounces per 100# 6.312
to obtain 23.3%of cementitious (entrained
air entrainment materials air)
2841 pounds27.000 cu.ft.
105.2 pounds per cubic foot
Average 7-day test results 1625 psi
Average 28-day test results 2750 psi
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EXAMPLE V
1 cu. yd. Batch wt. Abs. vol.
Cement 4.43 Sacks 416 pounds 2.126
Ash 208 " 1.449
Water 42.1 Gal. 351 " 5.628
Sand 2245 " 13.785
Saccharide additive 2.0 ounces per 100# 4.012
to obtain 14.9% of cementitious(entrained
air entrainment material air)
3220 pounds27.000 cu. ft.
119.3 pounds per cubic foot
Average 7-day test results 1520 psi
Average 28-day test results 2350 psi
EXAMPLE VI
1 cu. yd. Batch wt. Abs. vol.
Cement 5.6 Sacks 526 pounds 2.688
Ash 263 " 1.832
Water 33.5 Gal. 279 " 4.479
Sand 1686 " 10.352
20 Saccharide additive 8.0 ounces per 100# 7.469
to obtain 28.3% of cementitious(entrained
air entrainment material air)
2754 pounds27.000 cu. ft.
102 pounds per cubic foot
Average 7-day test results 1890 psi
Average 28-day test results 2855 psi
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EXAMPLE VII
1 cu. yd. Batch wt. Abs. vol.
Cement 5.6 Sacks 526 pounds 2.668
Water 41.2 Gal. 343 " 5.508
Sand 1928 " 11.838
Saccharide additive 7.2 ounces per 100# 4.012
to obtain 25.8~ of cementitious(entrained
air entrainment materials air)
2797 pounds27.000 cu. ft.
103.6 pounds per cubic foot
Average 7-day test results 1900 psi
Average 28-day test results 2930 psi
The foregoing is considered as illustrative only
of the principles of the invention. Further, since numerous
modifications and changes will readily occur to those
skilled in the art, it is not desired to limit the inven-
tion as explicitly described, all suitable modifications
and equivalents which may be resorted to, falling within
the scope of the invention.
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