| GENERAL
DESCRIPTION
|
|
Foamed concrete or lightweight concrete derived from Allied's aqueous foams are suitable for both
precast and
cast-in-place
applications.
Some of the highly insulative cementitious foams at densities 48 kg/m3(3
pcf) to 645 kg/m3(40 pcf) or higher can be used as block fills, lightweight
roof deck and void-fill materials. Good strength
characteristics with reduced weight make lightweight concrete based on Allied's aqueous foams suitable for structural and semi-structural applications such as lightweight partitions, wall and floor panels,
and lightweight blocks. Cementitious foams derived from Allied's premium systems are suitable for thin layer coating
applications where specific performance criteria are required.
Foamed concrete and foamed cement made with Allied's foam have very fine pore
structure, unlike that made with conventional proteinaceous and surfactant
foams. The pore structure of Allied's foams hardly show any sign of deterioration as the density
of the foamed cement decreases to below 160 kg/m3 (10 pcf). At densities below
160 kg/m3, the pore
texture of foamed cement derived from conventional foam agents becomes so coarse
that most of them show severe structural collapse.
The dynamic nature of Allied foam systems allows different foam rheology to be incorporated into the host
cement/concrete matrix to satisfy a wide range of slump loss requirements.
The inert
nature of Allied foam systems makes them
compatible
with different kinds of aggregates, fillers, extenders,
retarders, accelerators, colorants, hydraulic inorganics and many other
additives.
|
|
| Highlights
on Allied’s WORK with Foamed DECORATIVE STONES, Blocks and Foamed Panels
|
| (WE
PROVIDE FOAM PRODUCTS, FOAM MACHINERY AND TECH SERVICE IN
PROCESS & MIX DESIGNS) |
| Autoclaved aerated
concrete (AAC) was introduced in Europe over half a
century ago as a lightweight construction material. The key
features AAC has over conventional foamed concrete are significantly better strength and lower shrinkage/cracking.
However, most of the attempts over the last few decades to
introduce AAC to the US either failed or hardly made any signifcant
impact to the construction industry. The million of dollars of capital investment needed for
the manufacture of AAC over the
conventional precast plant is just one of the many reasons
reported in the literature. |
| Freshly
prepared decorative stone panels with low shrinkage and
non-cracking features are shown below: |
| 3.6
feet x 2.6 feet (1.1 meters x 0.8 meters) |
| Total
weight = 28 pounds or 12.7 kg. |
 |
| (the
blue center block was acid-etched showing the blue
decorative sand texture underneath) |
|
| Dimensions
of individual panel = 22" x 8" w. thickness of
0.25"-1.25" (0.56meter x 0.2meter w. thickness of
1.6cm-3.2cm) |
| (weight
per panel = 3.5 pounds (1.6 kg.) |
|
| Freshly prepared
cement/aggregate bricks/blocks derived from Allied's specialty foams
with high slump loss may even be extrudable and thus amenable for
mass production. A freshly cast foam brick at 37 pcf (600
kg/m3) without using any mould is shown below: |
| Freshly
Made Foam Cement Brick w. High Slump Loss (density = 37
pcf) |
Extruded
Foam Cement/Ltwt Aggregate Composite (density = 40 pcf,
compressive
strength = 660 psi (4.6 MPa)) |
Instantly
Demolded Cement/Ltwt Aggregate Composite (density = 31 pcf,
compressive
strength = 460 psi (3.2
MPa)) |
| (a
mould-free cast) |
(low
pressure extrusion) |
(demolded
in < 1 minute) |
|
|
|
|
| Highlights
on Allied’s WORK witH Geotechnical engineering, LANDSCAPE ARCHITECTURE AND SLOPED ROOF
DECK |
Composites with
Allied’s premium foamed cement/high
slump-loss/high strength 35 pcf foamed cement allows greater and
simpler landscape architecture and roof deck designs not achievable
by any conventional cellular concrete.
1.
Geotechnical Engineering & Landscape architecture
A. conventional
cellular concrete - conventional 35 pcf LDCC
(Low Density Cellular Concrete) with
shaved expanded polystyrene blocks.
Very limited slope
negotiation for conventional cellular concrete – less than
½ inch drop per 10 feet span. |
|
Geofoam/styrofoam blocks
of various sizes/shapes are needed to create artificial
slopes. |
|
Labor intensive and slow
process. |
B. New and flexible
designs with Allied’s high
slump-loss foamed cement
|
Highly sloped landscape with > 1 feet drop per 10 feet span can
easily be achieved. |
|
The use of Geofoam/styrofoam blocks is significantly reduced
or totally eliminated. |
|
Labor savings and faster process. |
| High Slump
Loss Foamed Cement/Lightweight Aggregate
Composites with Low Shrinkage at a Dry Density
of 35-50 pcf (565 - 806 kg/m3) |
|
|
 |
 |
| >
2.5 feet drop per 10 feet span (1V/4H) |
Full
Size Air Conditioner Pad From High Slump Loss/Low Shrinkage
Foamed Cement Composite |
|
(dry density = 35 pcf) |
(dry density = 48 pcf) |
|
Field Application of High
Slump Loss Foamed Cement Composite on Sloped Geofoam -
Harvard University NorthWest
Laboratories Project - High Slump Loss Foamed Concrete
(through Allied's Tech Service, Products & Machinery) - Completed in December, 2007.
|
|
The
210,000 square foot above-ground portion of the facility
(another 260,000 square feet will be below ground) will also
face Hammond and Gorham Streets, complemented by a landscape
designed by Michael Van Valkenberg Associates. |
 |
|
(Pre-project
mockup work by Allied Foam Tech is shown below) |
 |
 |
 |
 |
| Mixing
& Pumping of High |
Applying of
High Slump Loss |
Finished
Foamed Cement Crown |
Cross-section
of |
| Slump Loss
Foamed Cement |
Foamed
Cement on 1V/4H Slope |
On Highly
Sloped Geofoam |
Landscape
after ~ 1 year |
2. Improved Foamed Cement Roof
Deck Designs
Highly sloped industrial
and residential roofdecks or roofings become possible with Allied's
high slump-loss foamed cement product and mix design.
Allied's stable foam with
high slump loss can be applied directly on corrugated metal sheets
of new or repaired roofs without foam dewatering and possible water
leakage to the interior structure of the floors underneath while
such problems have always been associated with conventional cellular
concrete roof decks.
Using Allied’s 35pcf/10 pcf foamed cement
composite as roof deck structure will
achieve the right combination of thermal insulation and light weight
like
conventional cellular concrete/styrofoam blocks but with appreciable
labor and time savings and the flexibility in roof deck designs with varied shapes
and contours not achievable before.
Comparison of
Roof Deck Composites from Allied's Foamed Cement Composite &
Conventional Foamed Cement/Expanded Polystyrene Board Composite.
|
| Allied's
35 pcf/10 pcf Foamed Cement Composite |
Conventional
35 pcf Foamed Cement w. EPS Boards |
|
|
| a
brief comparison of KEY PROPERTIES BETWEEN ALLIED'S
FOAM/AGGREGATE
COMPOSITE AND AAC IS GIVEN BELOW: |
| |
Allied's
Foam/Aggregate Composite |
Autoclaved
Aerated Concrete (AAC) |
| Compressive
Strength (relative to conventional foamed
concrete) |
High |
High |
| Shrinkage/Cracking
(relative to conventional foamed concrete) |
Low |
Low |
| Water
Absorption (relative to conventional
foamed concrete) |
Lowest
in the industry |
High
(see
the figure on lower right)
|
| Window
for Concrete Processing Additives |
Compatible
w. various concrete additives, processing aids and
pigmentation |
Mostly
incompatible due to its aggressive steam curing condition |
| Foam
Density Available |
From
5 pcf to > 90 pcf |
Mostly in the 30 to 50
pcf range
(due to the limitation in its foaming process &
steam curing efficiency) |
| Method
of Production |
Precast,
cast-in-place & extrusion (with specific mix design & slump loss) |
Precast
only |
| Capital
Investment |
Similar
to a conventional precast plant |
Millions of $ over a conventional
precast plant
|
Allied's stable foam
products, low water/cement ratio with high range water reducer,
and the synergistic use of various lightweight aggregates and
other proprietary additives have
allowed foamed concrete that matches the compressive strength
of AAC with low shrinkage and crack-free. A recent client claims
that the use of Allied's foam products allows their lightweight
precast outperform all others in the market.
STRENGTH &
WATER RESISTANCE PROFILE AT 30 - 60 PCF (480 - 970 Kg/M3)
- Loadbearing (low
rise), semi-structural & non-loadbearing.
|
|
|
|
|
28 DAYS STRENGTH
PROFILE AT 55 - 80 PCF (890 - 1,290 Kg/M3) - loadbearing
andsemi-structural.
|
|
(The following data are derived from
mix designs that may have different slump loss characteristics from
that at 30 - 60 pcf)
|
| Density
(Air Dry) |
Compressive
Strength |
|
(pcf) |
(Kg/M3) |
(psi) |
(MPa) |
|
56 |
900 |
1,200 |
8.2 |
|
65 |
1,040 |
1,480 |
10.2 |
|
69 |
1,110 |
1,700 |
11.7 |
|
74 |
1,190 |
2,300 |
15.9 |
|
76 |
1,240 |
> 2,500 |
> 17.2 |
|
|
COMPOSITES AT 10 -
20 PCF (160 - 320 Kg/M3) - non-loadbearing
& insulative.
|
|
(WE
PROVIDE FOAM PRODUCTS, FOAM MACHINERY AND TECH SERVICE IN PROCESS
& MIX DESIGNS)
|
|
Even at densities as low as 10 pcf, the
strength development of Allied's foam/lightweight aggregate
composites allows <24 hours demolding time while still
maintaining good handling characteristics (all three blocks shown
below were demolded in 18-24 hours and were immediately saw-cut to
proper size)
|
|
|
10 pcf (160 Kg/M3)
15 pcf (240 Kg/M3)
18 pcf (290 Kg/M3)
|
|
Panels
and Blocks Based on Allied's Foam & Lightweight
Aggregate Mixes |
 |
 |
| 45
pcf
36 pcf
46 pcf |
Cross
Seection of Foam/Aggregate Panel |
 |
 |
|
|
Foam/Aggregate Blocks 35-45 pcf
(565 - 726 Kg/M3)
|
|
|
PERFORMANCE
|
| Some
Performance Features of Concrete and Cement Incorporating Allied's
Foam Systems: |
|
Consistent and fine pore texture at different densities
Low water uptake
Hight early and 28 day compressive strengths
Good thermal and acoustic properties
Wide range of rheological, adhesive and thin-set properties
|
|
uniform &
fine texture
non-uniform & coarse
texture
