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Specifying Cement for Use in Concrete
When is it appropriate to use a Type II cement?
Why is your customer requesting a Type IS cement?
What is a Type LH Cement?
What can be used in place of a Type III cement?
There
are many different properties and applications of cements for use
in concrete including; portland, blended, and hydraulic cements.
To help determine which cement is most appropriate for your construction
needs and to optimize mixture performance and economy it is important
to know what is available… we’ve come along way from
Joseph Aspdin’s patent in 1824!
When a cement is specified for a project, consideration should
be given to the types of material available in that location. The
specification should be flexible, allowing either portland or blended
cements. Consideration should always be given to the use of locally
available pozzolans and ground-granulated blast furnace slag, provided
the desired concrete properties can be achieved. Ideally, the specification
should allow any cement that meets the performance requirements
of the project. Cements with special or unique properties should
not be required unless absolutely necessary.
If
no special properties are required
The specification should permit the use of Types I and II
portland cement, blended cements, or any cement meeting the requirements
of a type GU hydraulic cement. The use of pozzolans or slags should
be permitted wherever possible. It may not be possible to use significant
levels of pozzolans or slag (or Types S or P blended cements), in
many applications because these concretes tend to set, harden, and
gain strength at a slower rate, especially in cold weather.
Heat of hydration requirements –
Where
moderate heat of hydration is required, Type II portland cement
meeting the moderate heat option can be used, as well as a blended
cement with the MH suffix, or any hydraulic cement meeting the requirements
of Type MH. The temperature requirements of the concrete may also
be met using other cements such as a Type I portland cement in combination
with sufficient amounts of pozzolan or slag.
Low
heat of hydration requirements can be met with a Type IV portland
cement (although generally not produced in the U.S.). A portland-pozzolan
cement meeting the low-heat option (Type P(LH) cement), or any hydraulic
cement meeting the requirements of Type LH will also provide a low
heat of hydration. Low heat can also be achieved by using suitable
supplementary cement materials.
For more details about selecting the right cement type to prevent
thermal stresses, see Portland
Cement, Concrete, and Heat of Hydration (PL972).
Where
sulfate resistance is required –
Moderate sulfate resistance can be provided by the appropriate portland
or blended cement or by any hydraulic cement meeting the requirements
of Type MS. The sulfate resistance of concrete can also be improved
by the appropriate use of pozzolans or slag.
High
sulfate resistance can be achieved with a Type V portland cement
or any hydraulic cement meeting the requirements of Type HS. Many
blended Type IS or IP blended cements will meet the requirements
for high sulfate resistance, but there is no specific classification
for these cements in ASTM C 595. Sulfate- resistant concrete may
also be met by using other cements such as a Type I portland cement
in combination with sufficient amounts of appropriate pozzolans
or slag.
High
early strength requirements-
High early strength requirements can be met by either a Type III
portland cement or a Type HE hydraulic cement. Blended cements containing
highly reactive pozzolans such as silica fume may also meet the
requirements for high early strength, although there is no specific
classification for such a cement in ASTM C 595.
Resistance to ASR-
When
a potentially reactive aggregate is being used some level of protection
against damaging ASR expansion may be achieved by specifying either
the low-alkali option for portland cement, the option for low-reactivity
with pyrex glass for blended cements, or by specifying any type
of hydraulic cement that meets option R (which also based on a performance
test using pyrex glass). Resistance to ASR may also be conferred
on a concrete by incorporating sufficient amounts of appropriate
pozzolans or slag.
Applications for Commonly Used Cements

*Check the local availability
of specific cements as all cements are not available everywhere.
**The option for low reactivity with ASR susceptible
aggregates can be applied to any cement type in the columns to the
left.
***For ASTM C 1157 cements, the nomenclature of
hydraulic cement, protland cement, air-entraining protland cement,
modified portland cement, or blended hydraulic cement is used with
the type designation.
(Kosmatka, S.H., Kerkhoff, B. and Panarese, W.C. Design
and Control of Concrete Mixtures. 14th Edition, EB001, Portland
Cement Association, 2002.)
Some types of portland cement may not be readily available in all
areas. Type I portland cement is usually furnished when a specific
cement type is not specified. Type II cement is usually available,
especially in areas of the country where moderate sulfate resistance
is needed. Cement Types I and II represent about 90% of the cement
produced. Some cements are designated as both Type I and II (Type
I/II), meaning that they meet specification requirements for both
types. Type III cement and white cement are usually available in
larger metropolitan areas. Type IV cement is manufactured only when
specified for particular projects (massive structures like dams),
and therefore is usually not readily available. Type V cement is
available only in particular regions where it is needed to resist
high sulfate environments.
Blended cements are available in many regions of the United States
but certain types may not available in some areas. The properties
conferred on concrete through the use of blended cements can usually
be attained by combining normal portland cement with appropriate
levels and types of supplementary cementing materials at the mixer.
When cements with special properties are not available, adjustments
to the proportions and types of material in concrete mix can usually
be made to attain the desired properties using available materials.
For
more information on cement types and application, refer to the latest
release in PCA’s highly-regarded series of interactive distance
learning training programs on cement and concrete technology, CD050,
Cements for Use in Concrete. This CD
provides a comprehensive overview of cements for use in general
concrete construction.
Cements
for Use in Concrete (CD050)
Topics include:
- The cement manufacturing process, including raw materials, grinding,
pyroprocessing, cooling, and finish grinding.
- Cement classification; portland and blended types.
- The primary effects cement properties have on fresh and hardened
concrete properties.
- Applicable specifications for cements for general concrete
construction: ASTM C 150, ASTM C 595, and ASTM C 1157.
For more information or to order click
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