U.S. patent application number 11/137487 was filed with the patent office on 2005-10-13 for method and apparatus for cooling concrete during curing.
This patent application is currently assigned to Dryair Inc.. Invention is credited to Bourgault, Claude, Dancey, Larry.
Application Number | 20050223717 11/137487 |
Document ID | / |
Family ID | 35059137 |
Filed Date | 2005-10-13 |
United States Patent
Application |
20050223717 |
Kind Code |
A1 |
Bourgault, Claude ; et
al. |
October 13, 2005 |
Method and apparatus for cooling concrete during curing
Abstract
A system and method for cooling a concrete slab to improve
curing in hot weather includes a portable liquid cooler. A conduit
is connected to the liquid cooler and arranged in proximity to the
concrete slab. A pump is operative to circulate liquid from the
liquid cooler through the conduit such that liquid moves from a
supply port of the liquid cooler into an input end of the conduit
at a supply temperature, moves through the conduit, and moves from
an output end of the conduit to a return port of the liquid cooler
at a return temperature greater than the supply temperature. Heat
is absorbed from the concrete slab and the temperature of the slab
is thus reduced compared to a slab in ambient hot weather
conditions.
Inventors: |
Bourgault, Claude; (St.
Brieux, CA) ; Dancey, Larry; (Melfort, CA) |
Correspondence
Address: |
NIXON & VANDERHYE, PC
901 NORTH GLEBE ROAD, 11TH FLOOR
ARLINGTON
VA
22203
US
|
Assignee: |
Dryair Inc.
St. Brieux
CA
|
Family ID: |
35059137 |
Appl. No.: |
11/137487 |
Filed: |
May 26, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11137487 |
May 26, 2005 |
|
|
|
10751455 |
Jan 6, 2004 |
|
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Current U.S.
Class: |
62/62 |
Current CPC
Class: |
E01C 23/03 20130101;
F25D 2400/12 20130101; F25B 41/40 20210101; F25B 15/00 20130101;
B28B 7/42 20130101 |
Class at
Publication: |
062/062 |
International
Class: |
E04C 003/00 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 31, 2004 |
CA |
2,479639 |
Aug 26, 2004 |
CA |
2,479720 |
Claims
What is claimed is:
1. A system for cooling a concrete slab to improve curing in hot
weather, the system comprising: a portable liquid cooler; a conduit
connected to the liquid cooler and adapted to be arranged in
proximity to the concrete slab; a pump operative to circulate
liquid from the liquid cooler through the conduit such that liquid
moves from a supply port of the liquid cooler into an input end of
the conduit at a supply temperature, moves through the conduit, and
moves from an output end of the conduit to a return port of the
liquid cooler at a return temperature greater than the supply
temperature.
2. The system of claim 1 wherein the conduit is flexible and
adapted to be arranged in loops on a surface of the concrete
slab.
3. The system of claim 1 wherein the conduit is adapted to be
arranged in loops and embedded in the concrete slab.
4. The system of claim 1 further comprising: a first manifold
operatively connected to the supply port of the liquid cooler; a
second manifold operatively connected to the return port of the
liquid cooler; a plurality of conduits each having an input end
operatively connected to the first manifold and an output end
operatively connected to the second manifold.
5. The system of claim 1 wherein the portable liquid cooler
comprises an absorption chiller.
6. The system of claim 1 comprising an insulation layer configured
to substantially cover the concrete slab.
7. A method of cooling a concrete slab to improve curing in hot
weather, the method comprising: providing a portable liquid cooler
adjacent to the concrete slab; connecting a conduit the liquid
cooler and arranging the conduit in proximity to the concrete slab;
with a pump, circulating liquid from the liquid cooler through the
conduit such that liquid moves from a supply port of the liquid
cooler into an input end of the conduit at a supply temperature,
moves through the conduit, and moves from an output end of the
conduit to a return port of the liquid cooler at a return
temperature greater than the supply temperature.
8. The method of claim 7 wherein the conduit is flexible and
arranged in loops on a surface of the concrete slab.
9. The method of claim 7 wherein the conduit is arranged in loops
and embedded in the concrete slab.
10. The method of claim 7 further comprising: providing a first
manifold operatively connected to the supply port of the liquid
cooler; providing a second manifold operatively connected to the
return port of the liquid cooler; providing a plurality of conduits
each having an input end operatively connected to the first
manifold and an output end operatively connected to the second
manifold, and circulating liquid from the supply port of the liquid
cooler into the first manifold to the input end of each conduit,
through each conduit, and from the output end of the conduit to the
return port of the liquid cooler.
11. The method of claim 7 wherein the portable liquid cooler
comprises an absorption chiller.
12. The method of claim 7 comprising covering the concrete slab
with an insulation layer.
Description
[0001] This invention is in the field of laying concrete, and
particularly laying concrete in warm weather.
BACKGROUND
[0002] Maintaining the temperature of concrete at a satisfactory
level during curing presents considerable challenges because of the
wide ambient temperatures encountered when laying concrete. The
American Society for Concrete Contractors recommends that the
temperature of the concrete be maintained between 50 and 70.degree.
F. It is well known that concrete must be kept above freezing
during curing when the weather is cold.
[0003] Similarly, when the weather is hot, the concrete can dry too
quickly. As happens with concrete that freezes before curing,
concrete that is too warm dries too quickly and so suffers from
reduced strength and is subject to cracking. This problem is
exacerbated by the heat generated within a freshly poured concrete
slab, wall or the like by the chemical reactions of the curing
process.
[0004] Proper curing of concrete can affect the final strength by
several-fold, and so significant attention is paid to maintaining a
desirable temperature and level of hydration of the freshly poured
concrete in order that the curing process will be the most
effective, and the finished concrete product will display the
highest degree of strength.
[0005] It is well known to circulate hot liquid, such as hot water
or a water/glycol mix, through a conduit arranged on a freshly laid
concrete surface in order to prevent the concrete from freezing,
and maintain the concrete at a temperature within the preferred
temperature range for curing. Typically the conduit comprises
flexible hoses are laid out in a back and forth pattern on the
surface, with a spacing of 30-60 centimeters. It is also known to
embed the hoses in the concrete to increase efficiency by better
retaining and distributing the heat in the concrete. These hoses
then remain in the finished concrete and are sacrificed, or in some
cases are used to heat the finished building by circulating hot
water through them.
[0006] In hot climates, ice is sometimes mixed with the concrete to
reduce the temperature. Also it is known to circulate carbon
dioxide gas through hoses similar to the above in order to cool the
concrete.
SUMMARY OF THE INVENTION
[0007] It is an object of the present invention to provide a method
and apparatus for cooling concrete in hot weather that overcomes
problems in the prior art.
[0008] In a first embodiment the invention provides a system for
cooling a concrete slab to improve curing in hot weather. The
system comprises a portable liquid cooler. A conduit is connected
to the liquid cooler and adapted to be arranged in proximity to the
concrete slab. A pump is operative to circulate liquid from the
liquid cooler through the conduit such that liquid moves from a
supply port of the liquid cooler into an input end of the conduit
at a supply temperature, moves through the conduit, and moves from
an output end of the conduit to a return port of the liquid cooler
at a return temperature greater than the supply temperature.
[0009] In a second embodiment the invention provides a method of
cooling a concrete slab to improve curing in hot weather. The
method comprises providing a portable liquid cooler adjacent to the
concrete slab, and connecting a conduit the liquid cooler and
arranging the conduit in proximity to the concrete slab. With a
pump, liquid is circulated from the liquid cooler through the
conduit such that liquid moves from a supply port of the liquid
cooler into an input end of the conduit at a supply temperature,
moves through the conduit, and moves from an output end of the
conduit to a return port of the liquid cooler at a return
temperature greater than the supply temperature.
[0010] The liquid circulating through the conduit adjacent to the
concrete slab absorbs heat from the slab and reduces the
temperature of the slab. Drying of the concrete is slowed to
improve curing and increase the strength of the finished slab.
DESCRIPTION OF THE DRAWINGS
[0011] While the invention is claimed in the concluding portions
hereof, preferred embodiments are provided in the accompanying
detailed description which may be best understood in conjunction
with the accompanying diagrams where like parts in each of the
several diagrams are labeled with like numbers, and where:
[0012] FIG. 1 is a schematic top view of a system of the invention
for cooling a concrete slab to improve curing in hot weather using
a single conduit;
[0013] FIG. 2 is a schematic top view of a system of the invention
for cooling a concrete slab to improve curing in hot weather using
manifolds connected to a plurality of conduits.
DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS
[0014] FIG. 1 schematically illustrates a system for cooling a
concrete slab 2 to improve curing in hot weather. The system
comprises a portable liquid cooler 4 having a supply port 6 and a
return port 8. The cooler 4 is conveniently an absorption chiller
that is conveniently portable and can be operated on fuel such as
diesel or propane such that a significant electrical power supply
is not required. The cooler 4 is operative to cool liquid entering
the return port 8 such that the temperature of the liquid entering
the return port 8 is greater than the temperature of liquid leaving
the supply port 6.
[0015] A conduit 10 is connected to the supply and return ports 6,
8 of the liquid cooler 4 and is arranged in proximity to the
concrete slab 2. In the system illustrated in FIG. 1 the conduit 10
is flexible and arranged in loops on the surface of the concrete
slab 2. Alternatively the conduit 10 could be embedded in the
concrete slab 2. Once the concrete has cured, the liquid cooler 4
is disconnected from the conduit 10, which is then left in
place.
[0016] A pump 12 is operative to circulate liquid from the supply
port 6 of the liquid cooler 4 into an input end of the conduit 10
at a supply temperature, through the conduit 10, and from an output
end of the conduit 10 to the return port 8 of the liquid cooler 4
at a return temperature that is greater than the supply
temperature.
[0017] The cool liquid entering the conduit absorbs heat from the
concrete slab as it moves through the conduit 10 such that the
temperature thereof increases between the input and output ends of
the conduit 10. As the liquid passes through the cooler 4, the
temperature of same is reduced to the supply temperature. The
system essentially pumps heat out of the concrete to maintain the
concrete slab 2 at a reduced temperature compared to the ambient
temperature. Drying time and curing time thus increase, improving
the strength of the concrete slab 2.
[0018] For best results a blanket or like insulation layer will
typically be spread over the conduit 10 and concrete slab 2 in
order to reduce the amount of heat absorbed by the cooled liquid
from the atmosphere, and thus increase the amount of heat absorbed
from the slab 2.
[0019] FIG. 2 illustrated the system of FIG. 1 with the addition of
a supply manifold 20A operatively connected to the supply port 6 of
the liquid cooler 4, and a return manifold 20B operatively
connected to the return port 8 of the liquid cooler 4. A plurality
of conduits 10 each has an input end 10A operatively connected to
the supply manifold 20A and an output end 10B operatively connected
to the return manifold 20B.
[0020] Thus in the system of FIG. 2, cooled liquid enters the input
ends 10A of each conduit 10 at the supply temperature and leaves
the output ends 10B thereof at the return temperature. The capacity
of the pump 12 is increased such that, for example, where the pump
12 in FIG. 1 might pump 100 liters per minute (l/m) through the
single conduit 10, the pump 12 in FIG. 2 would pump 200 l/m to the
supply manifold 20A, and each conduit 10 would carry 100 l/m to the
return manifold 20B such that 200 l/m is returned to the return
port 8. Thus the liquid moves through the conduits 10 at the same
speed as in FIG. 1, but for a shorter distance such that liquid in
each conduit 10 absorbs less heat before returning to the return
port 8 and the temperature increase of the liquid is therefore
reduced, and the return temperature is less than it is in the
system of FIG. 1.
* * * * *