Durability
Concrete
Technology Home > Durability Durability is the ability
of concrete to resist weathering action, chemical attack, and abrasion
while maintaining its desired engineering properties. Different
concretes require different degrees of durability depending on the
exposure environment and the properties desired. Concrete ingredients,
their proportioning, interactions between them, placing and curing
practices, and the service environment determine the ultimate durability
and life of the concrete.
Exposure Conditions and Deterioration Mechanisms
The table below shows important exposure conditions
and deterioration mechanisms in concrete structures. In practice,
several of these deterioration mechanisms can act simultaneously
with possible synergistic effects.
Guide To Durable Concrete
 Different
concretes require different degrees of durability depending on the
exposure environment and the properties desired.
The Specifer’s Guide for Durable Concrete is
intended to provide sufficient information to allow the practitioner
to select materials and mix design parameters to achieve durable
concrete in a variety of environments.
Addressing Durability with the Prescriptive or Performance Approach
Durability of concrete can be addressed by two approaches. The first
is called the “prescriptive” approach, where designers
specify materials, proportions, and construction methods based on
fundamental principles and practices that exhibit satisfactory performance.
The second is called the “performance” approach, where
designers identify functional requirements such as strength, durability,
and volume changes, and rely on concrete producers and contractors
to develop concrete mixtures to meet those requirements. Performance
specifications define performance for a given exposure and life
expectancy, and include tests, which are tied to the field performance
of concrete. Refer to NRMCA’s Performance-Based
Specifications for Concrete for details. Very often a specification
will contain prescriptive as well as performance elements. Click
here for durability requirements of the 2008 ACI 318 Building Code.
Case Studies
 Confederation
Bridge. Concrete used for the Confederation Bridge across
the Northumberland Strait between Prince Edward Island and New Brunswick
was specifically designed for high durability in a severe environment.
The bridge has to resist freezing and thawing, seawater exposure,
and abrasion from floating ice. With a design life of 100 years,
the use of high performance concrete and careful attention to production
and construction practices were imperative. Over 400,000 cubic meters
(520,000 cubic yards) of concrete was used for the structure. More.
 Wacker
Drive. Determined to build maximum durability into the
heavily traveled Wacker Drive thoroughfare, the City of Chicago
set an ambitious goal: a 75- to 100-year design life of the structure.
The material of choice? High-performance concrete. According to
Paul Krauss, senior consultant with WJE, the mix was designed with
the goal of maximizing durability, not compressive strength. More.
Concrete in the Marine Environment—Treat
Island Marine Exposure Site
 Located
on the Bay of Fundy near Eastport, Maine, the Treat Island exposure
station was established by the US Army Corps of Engineers (USACE)
in 1936 to study concrete durability in long-term programs. The
exposure site inherently imposes a unique combination of natural
severe environmental conditions ideally representative of severe
field exposure conditions.
Under the heading of “Improved Durability
of Concrete,” the field exposure durability studies at Treat
Island have provided data useful in determining concrete’s
resistance to frost attack, alkali-aggregate reaction, sulfate attack,
and corrosion of steel with variable cementitious types and contents,
aggregate types, chemical admixtures, and water-cementitous ratios.
More.
Preventing Joint Deterioration
 Concrete
provides a durable, attractive paved surface for roads. It provides
a longer life than any other leading paving materials and does not
rut or shove due to traffic or warm temperatures. Concrete’s
higher reflectance keeps surfaces cooler, helps minimize the urban
heat island effect, and can lower infrastructure and ongoing lighting
costs, while boosting safety for vehicles and pedestrians.
Some pavements in northern states have exhibited joint deterioration:
the premature disintegration of concrete around the joint. This
deterioration typically begins to show after several years in place.
The mechanism behind joint deterioration is complex and is understood
to have basis in freeze-thaw damage and mechanical damage. More.
References
Detwiler, R. J., and Taylor, P. C., Specifier’s
Guide to Durable Concrete, EB221, Portland Cement Association,
Skokie, Illinois, USA, 2005, 68 pages.
References related to:
Kerkhoff, Beatrix, Effects
of Substances on Concrete and Guide to Protective Treatments,
IS001, Portland Cement Association, 2001, 36 pages.
Miller, F. M.; Detwiler, R.; and Powers, L.,
Investigation of Deteriorated Concrete in Pavement, Portland
Cement Association, Skokie, Illinois, August, 2000.
Pavement Durability:
A Case Study, Concrete Technology Today, Vol. 21, No. 2,
CT002, Portland Cement Association, Skokie, Illinois, July, 2000
SHRP,
Distress Identification Manual for the Long-Term Pavement Performance
Project. SHRP-P-338, Strategic Highway Research
Program, Washington, DC, 1993
Sutter, L. L.; Peterson, K. R.; Van Dam, T. J.; Smith, K. D. and
Wade, M. J.; Guidelines for Detection, Analysis, and Treatment
of Materials-Related Distress (MRD) In Concrete Pavements
- Guidelines for Detection, Analysis, and Treatment of MRD in
Concrete Pavements Vol I – Final
Report,
FHWA-RD-01-163, March 2002.
- Guidelines for Detection, Analysis, and Treatment of MRD in
Concrete Pavements Vol II – Guidelines
Description and Use, FHWA-RD-01-164, March 2002.
- Guidelines for Detection, Analysis, and Treatment of MRD in
Concrete Pavements Vol III – Case
Studies,
FHWA-RD-01-165, March 2002.
PCA, Types and
Causes of Concrete Deterioration, IS536, Portland Cement
Association, 2002.
PCA, Concrete
Slab Surface Defects: Causes, Prevention, Repair, IS177,
Portland Cement Association, 2002
PowerPoint Presentations/Images
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Library
Search PCA’s library, which include over 22,000 books, reports,
standards, journals, electronic documents, and videos.
A list of many of the durability-related publications may be found
HERE.
Although library loans are available only to PCA Members, the Library
staff is happy to assist nonmembers in obtaining items through interlibrary
loan.
In addition, the Library has access to many technical databases
and can provide literature searches on particular aspects of durability.
The result is a bibliography, often with abstracts, of articles,
conference papers, reports, patents, and other literature on that
topic. If the requestor then requires copies of the actual papers,
the Library can provide that as well.
Major journals addressing durability issues include ACI Materials
Journal, Cement and Concrete Research, Cement and Concrete
Composites, Concrete International, Concrete Producer, Materials
and Structures. For subscription information, contact the Library
at library@cement.org.
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