Precast Concrete Codes and
Standards
Which ones apply to the products
you design?
By Dean A. Frank, P.E.
Dean Frank is
Director of Technical Services at NPCA.
Involvement in the precast
concrete industry requires knowledge of the
many codes and standards that govern how precast
concrete products are designed and produced.
Given the multitude of such codes and standards,
including those produced by the International
Code Council (ICC), American Concrete Institute
(ACI) and ASTM International, it’s easy
to see how uncertainty can arise. There are
important distinctions between each of these,
which the designer should understand.
Building Codes
In the United States
there are several building codes that have been
adopted by state and local authorities and have
recently been consolidated into those managed
by the ICC. Code-making bodies that are now
part of the ICC include the Building Officials
and Code Administrators International Inc. (BOCA),
International Conference of Building Officials
(ICBO) and Southern Building Code Congress International
Inc. (SBCCI). These codes often refer to specifications
produced by both ACI and ASTM.
ACI
The American Concrete
Institute produces several large volumes of
technical documents, reports, guides, specifications
and codes for the best use of concrete. The
best known for reinforced concrete is ACI 318,
“Building Code Requirements for Structural
Concrete.” This code covers the proper
design and construction of buildings consisting
of structural concrete and provides the foundation
for the vast majority of cast-in-place reinforced
concrete design. However, it does cover structural
precast concrete elements as well. An example
of one variation in ACI 318 requirements for
precast vs. cast-in-place involves concrete
protection for reinforcement. The concrete cover
requirements for precast concrete members are
less than those required for cast-in-place concrete.
This is because precast concrete products are
typically produced in a quality-controlled environment
in which greater control of mix proportioning,
placing and curing are achieved and reinforcing
steel placement is usually more precise. Precast
concrete products that are typically covered
by ACI 318 include any product that becomes
part of a building or structure, such as a beam,
column, decking or wall panel.
Because ACI 318 contains
the general principles for reinforced concrete
design, one common misconception is that it
applies to ALL reinforced concrete. However,
this is not necessarily the case since it is
a structural building code. Nonetheless, in
the absence of another specification, ACI 318
can be used to provide a reliable and conservative
design.
ASTM
Standards developed under the auspices of ASTM
International (formerly known as the American
Society for Testing and Materials, or just ASTM)
are often used in the precast concrete industry
- more so than any other code or specification.
ASTM standards provide the basis for design
and production of many precast concrete products
that are not a part of a building or structure
and that are consequently not directly covered
by ACI 318. These products include manholes,
concrete pipe, box sections and three-sided
structures for culverts, storm drains and sewers;
highway barriers; architectural cast stone;
crib wall members; utility structures; and water
and wastewater structures.
More than 10,000 ASTM standards
are published each year in the 73 volumes of
the Annual Book of ASTM Standards. Volumes 4.02,
“Concrete and Aggregates,” and 4.05,
“Chemical-Resistant Nonmetallic Materials;
Vitrified Clay Pipe; Concrete Pipe; Fiber-Reinforced
Cement Products; Mortars and Grouts; Masonry,”
contain the majority of the standards that pertain
to the precast concrete industry.
ASTM standards contain common
language that promotes the flow of goods between
buyer and seller and protects the general welfare
of all parties. ASTM standards also create a
level playing field among producers of like
products.
ASTM standards are voluntary
consensus standards developed primarily to ensure
the proper production, use and testing of a
material or product. In the United States, the
standards development system is called “voluntary”
for two reasons. First, participation in the
system is voluntary. Second, the standards produced
usually are intended for voluntary use. Voluntary
consensus standards are developed through the
participation of all interested stakeholders
including producers, users, consumers and representatives
of government and academia. This ensures technical
competency of the standard and that it has a
high degree of credibility when critically examined
and used as the basis for commercial, legal
or regulatory initiatives.
In the United States, the
distinction between voluntary and mandatory
standards is not clear-cut. Often, government
standards developers refer in their regulations
to privately developed standards, and in that
reference give the standard the force of federal,
state or local law.
How
do ASTM standards differ from building codes?
ASTM standards are different from building codes
in that the standards are written to address
specific issues, such as a product specification,
a test method or a construction practice. They
are brief and specific in nature. An advantage
over building codes is that ASTM standards can
be developed much quicker, and new standards
can easily be created whenever an industry need
is identified.
As mentioned previously, building
codes generally reference hundreds of standards
that have been developed by voluntary standards
organizations. Since building codes are generally
the province of government, the referenced standards
in turn have the force of law and must be followed.
Generally, nonstructural precast
concrete products are not required to meet building
codes because they reside outside of the building
envelope. However, many precast concrete products
must instead meet the requirements of specific
ASTM standards. Often, the ASTM standard will
either refer to all or a portion of ACI 318
or specify the actual construction requirements
in the text of the specification. It should
be noted that ASTM standards represent minimum
requirements for common service conditions and
that additional reinforcement, etc., may be
necessary for a product to perform adequately
in less-common conditions.
No matter which code or standard
is used for precast concrete products, one thing
is clear: Each will ensure that the inherent
quality, value and permanence of precast concrete
is preserved.
References
For more information on precast codes and standards,
please contact:
International
Code Council
5203 Leesburg Pike, Suite 600
Falls Church, VA 22041
Phone: (703) 931-4533
Fax: (703) 379-1546
www.iccsafe.org
American
Concrete Institute
38800 Country Club Drive
Farmington Hills, MI 48331
Phone: (248) 848-3700
Fax: (248) 848-3701
www.aci-int.org
ASTM
International
100 Barr Harbor Drive
West Conshohocken, PA 19428-2959
Phone: (610) 832-9585
Fax: (610) 832-9555
www.astm.org
National
Precast Concrete Association
10333 N. Meridian St., Suite 272
Indianapolis, IN 46290
Phone: (800) 366-7731
Fax: (317) 571-9500
www.precast.org
