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Standards and
Approvals
Autoclaved aerated concrete (AAC) products are used
worldwide in various climates and environments from the salty air of the French
Riveria to the frigid regions of Finland and Switzerland. At SafeCrete, our products are
required to meet exacting standards.
We helped found the Autoclaved Aerated Concrete Products Association
(AACPA) to standardize AAC products in the United States, promote the
industry, and assist with consumer education. Our AAC products have been undergone the following
testing and have obtained NES and ICC approval.
The following tests were performed on various AAC products in accordance with the methods prescribed by the
American Society for Testing and Materials (ASTM).
View ASTM tests/reports
ASTM C 140 - ASTM
C 426 - ASTM E 72 - ASTM E 90
- ASTM E 119 - ANSI / UL 263
- ASTM E 447 - ASTM E 514 -
ASTM E 518 - ASTM E 519
ASTM C 140
"Sampling and Testing Concrete Masonry Units"
Certain physical characteristics of the AAC blocks are
important for the environmental design of a building. This test method
provides the means for the proper sampling and testing of AAC blocks in
order to determine their absorption. The absorption determined by this test
method was 11.9 pcf for AC2 and 12.1 pcf for AC4. Further absorption
characteristics are described in Chapter Vll - Construction Physics,
Section C "Moisture Behavior."
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ASTM C 426
"Drying Shrinkage of Concrete Masonry Units"
When designing and constructing buildings, an allowance
must be made for the normal drying shrinkage of the construction as the
materials stabilize to their final environmental conditions. If this
typical drying shrinkage is not properly compensated for, cracking may
result at restrained locations around the building envelope.
This test method provides a standardized procedure for
determining the drying shrinkage of the AAC blocks, as well as other
concrete products, when dried according to certain accelerated conditions.
The drying shrinkage, expressed as a percentage, is the change in length of
the test specimen due to drying from a saturated condition to an equilibrium
weight and length when subjected to the prescribed accelerated drying
conditions.
Tests were run on AAC blocks using AC2 and AC4 strength
categories. Drying shrinkages of 0.060% and 0.039% were determined
respectively for the AC2 and AC4 strength categories.
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ASTM E 72
"Standard Methods of Conducting Strength Tests of
Panels for Building Construction"
In order to achieve the proper structural design of a
building for wind loads, the flexural bending strength of the basic
structural elements used in the construction must be known. This test
method provides a basis for obtaining the flexural bending strength by
means of the application of a uniform pressure to the entire test wall
surface, simulating wind pressure on the actual construction.
The test specimen walls were constructed using nominal 8
inch (20cm) thick AAC blocks, with dry densities of 25 pcf (AC2) and 31 pcf
(AC4), in a running bond pattern, for determining the flexural tensile strength
perpendicular to the wall bed joints. A large air bag was placed between
the specimen and a reaction frame. The air pressure within the bag was
increased until failure of the specimen occurred. The failure pattern of
each specimen was noted and the ultimate flexural tensile strength,
standard deviation and coefficient of variation were calculated. The
average flexural tensile strength of both densities was virtually
identical. The failure mode for flexure is reproducible and controlled by
the precision block material rather than the mortar joint.
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ASTM E 90
"Laboratory Measurement of Airborne Sound
Transmission Loss of Building Partitions"
The performance of walls, floors and other building
assemblages in reducing the sound from one side of the assemblage to the
other is important in terms of the comfort of the occupants of the
building, whether it is a single family residence or a multi-story office
structure. This test method measures the sound transmission loss in decibels
(dB) in the frequency range of 125 to 4000 hertz.
Two separate tests were performed, one on a nominal 8
inch (20 cm) thick AC4 AAC block wall coated with 1/2 inch of lightweight
stucco on the outside and 1/4 inch of gypsum based plaster on the inside
and the second on a nominal four-inch (10 cm) AC6 AAC Wall Panel wall with
both surfaces coated with 1/4 inch of cement based smoothing compound. The
nominal 8 inch thick wall achieved a Sound Transmission Class (STC) rating
of 44 and the nominal 4 inch thick wall achieved a Sound Transmission Class
(STC) rating of 36.
ASTM E 119
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"Standard Test Methods for Fire Tests of Building
Construction and Materials"
The performance of walls, floors and other building assemblages
under exposure to fire is important for the safety and security of the
occupants of the building, their belongings and the building contents. This
test method measures the fire-resistive properties of the assemblage
materials when subjected to a standard fire exposure and provides for a
relative measure of the ability of the assemblage to prevent the spread of
the fire. After the assemblage is subjected to the standard fire exposure,
it is subjected to a standard fire hose stream of water, intended to
simulate the effects of fire fighting efforts. The assemblage must
successfully pass both portions of the test in order to achieve a certain
fire rating.
Testing was performed on two walls, one constructed of 4
inch (10 cm) thick AAC wall panels and one of nominal 8 inch (20 cm) thick
AAC blocks. The materials were assembled into typical wall panels,
approximately 10 feet high and 11 feet wide. The 4 inch thick wall panels
performed satisfactorily for a Fire Resistance Rating of 3 hours and 10
minutes. The 8 inch thick precision block wall performed satisfactorily for
a Fire Resistance Rating of 6 hours and 6 minutes.
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ANSI / UL 263
"Standard for Fire Tests of Building Construction
and Materials"
The performance of the roof, floors and walls under
exposure to fire is important for the safety and security of the occupants
of the building, their belongings and the building contents. This standard
test method determines the restrained and unrestrained rating for roofs and
floors and the bearing and nonbearing rating for walls when subjected to a
standard fire exposure with a superimposed load, simulating the maximum
loaded condition. The Standard provides for a relative measure of the
ability of the assemblage to prevent the spread of the fire and retain its
structural integrity. After the assemblage is subjected to the standard
fire exposure, it is subjected to a standard fire hose stream of water,
intended to simulate the effects of fire fighting efforts. The assemblage
must successfully pass both portions of the test in order to achieve a
certain fire rating.
Two AAC panel assemblages, UL K910 (8 inch thick floor
panel assemblage) and UL P933 (8 inch thick roof panel assemblage), were
tested. Both assemblages achieved a Restrained Assembly Rating of 4 hours
(using Type 1 panels) and an Unrestrained Assembly Rating of 1 hour (using
Type 1 panels) and 1-1/2 hours (using Type 2 panels). The two types of
panels tested had a different minimum amount of cover over the reinforcing;
Type 1 with a minimum cover of 20 mm and Type 2 with a minimum cover of 45
mm. Restraint was provided by means of a poured-in-place, reinforced,
concrete ring beam around the perimeter of the test assemblage. By virtue
of the types of panels tested, (i.e. the minimum panel thickness of 8 inch,
the cover over the reinforcing and the maximum reinforcing possible for a
panel), 10 inch and 12 inch roof and floor panel assemblages also have the
same Restrained Assembly and Unrestrained Assembly ratings.
An AAC block wall assemblage, UL U921, achieved a 4 hour
Bearing Wall Rating and a 4 hour Nonbearing Wall Rating with a minimum 6
inch thickness a Strength Class of AC6/650. Based upon the thermal
properties of this Strength Class, the remaining Strength Classes also have
the same Bearing Wall Rating and Nonbearing Wall Rating of 4 hours.
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ASTM E 447
"Compressive Strength of Masonry Prisms"
In order to achieve the proper structural design of a
building for gravity loads, the compressive strength of the masonry
assemblage must be accurately known. This test method provides a basis for
obtaining this engineering property by the application of a compressive
load to the prism by means of a spherically seated, hardened metal bearing
block above the specimen and a hardened metal bearing block below the
specimen. This ensures that a concentric load is applied uniformly over the
entire area of the prism. The results of the tests provide the engineering
design property known as the minimum compressive strength of masonry (f'm).
The minimum compressive strength of masonry is then used in the
determination of the allowable axial stress, the allowable compressive
bending stress and the compression moment resisting capacity of AAC block
assemblages.
The results of this test method determined that the
minimum compressive strength of masonry (f'm) was 348 psi for AC2, 580 psi
for AC4 and 870 psi for AC6.
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ASTM E 514
"Standard Test Method for Water Penetration and
Leakage Through Masonry"
Buildings must perform well under severe weather
conditions including frequent, intense thunderstorms accompanied by high
winds. The wall systems used in typical building construction must be able
to stop the rain from getting into the interior of the building envelope.
This test method provides a means whereby an entire wall
assembly is subjected to an application of water equivalent to 138 l/m2
(3.4 gal/ft2) per hour with an air pressure of 500 Pa (10 lbf/ft2) - which
is equivalent to a 62 mph wind force and 51/2 inches of rain per hour. Test
walls were constructed of AC2 strength category block and of AC4 strength
category block. Under these severe test conditions, no water passed through
any of the test walls of either strength category.
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ASTM E 518
"Standard Test Methods for Flexural Bond Strength
of Masonry"
The two methods delineated in this standard cover the
determination of the flexural bond strength of unreinforced masonry
assemblages. Both test methods utilize a masonry prism as a simply
supported beam, uniformly loaded by means of an air bag in one method and
third-point loaded in the other. The failure load is then used in
calculating the gross area modulus of rupture. A series of tests were run
using nominal 8 inch (20 cm) thick AAC block in the AC2 and AC4 strength
categories.
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ASTM E 519
"Standard Test Method for Diagonal Tension (Shear)
in Masonry Assemblages"
In order to achieve the proper structural design of a
building for resisting lateral wind loads by means of shear walls, the
strength and rigidity of the basic structural elements used in the shear
wall construction must by accurately known. The test method presented in
this standard provides an accurate means to measure the diagonal tensile
(shear) strength of masonry assemblages. The specimen size permits a
reasonable evaluation of the shear strength that would be representative of
a full-size masonry wall used in actual construction. The masonry
assemblages are loaded in compression along one diagonal of the specimen.
This results in a diagonal tension failure with the specimen splitting
apart in a direction parallel to the load application.
The test specimen walls were constructed using nominal 8
inch thick AAC block, strength categories of AC2 and AC4, in a running bond
pattern. The specimens were then placed into the testing machine with
diagonal axis positioned in a vertical manner. The load on the specimen was
increased until failure of the specimen occurred.
The failure pattern of each specimen was noted and
average shear strength, standard deviation and coefficient of variation
were calculated. The reproducible failure mode indicated that the strength
of the AAC block controlled the shear failure performance. This is in contrast
to the failure of the mortar joints, which is common in typical clay and
concrete masonry unit construction.
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