through a No 200 sieve (200 meshes to the linear inch, or 40,000 openings per square inch). Regardless of the
manufacturer, portland cement is the standard for the trade.
American Society for Testing and Materials (ASTM) Types
ASTM specifications cover five types of portland cements in ASTM CI50, "Standard Specifications for Portland
Cement."
Type I. This is a general-purpose cement of concrete that does not require any special properties of the
other types. In general, it is intended for concrete that is not subjected to sulfate attack or when the heat
of hydration will not cause too much of a temperature rise. Type I portland cement is used in pavement
and sidewalk construction, reinforced-concrete buildings and bridges, railways, tanks, reservoirs, sewers,
culverts, water pipes, masonry units, and soil and cement mixtures. It is more available than the other
types. Type I cement will reach its design strength in 28 days.
Type II. This is modified to resist a moderate sulfate attack. It usually generates less heat of hydration
and at a slower rate than Type I. Typical applications are drainage structures, where the sulfate
concentrations in either the soil or groundwater are higher than normal but are not severe, and large
structures in which its moderate heat of hydration produces only a slight temperature rise in the concrete.
However, temperature rise can be a problem when concrete is placed in warm weather. Type I cement
will reach its design strength in 45 days.
Type III. This is a high, early strength cement that produces strengths at an early age, usually seven days
or less. It has a higher heat of hydration and is more finely ground than Type I. Type III permits fast
form removal and, in cold weather construction, reduces the period of protection against low
temperatures. Although richer mixtures of Type I can obtain high early strength, Type III produces it
more satisfactorily and more economically. Use it cautiously in concrete structures having a minimum
dimension of 2 1/2 feet or more because the high heat of hydration can cause shrinkage cracking.
Type IV. This cement is a very special cement. It has a low heat of hydration intended for applications
requiring a minimal rate and amount of heat of hydration. Its strength also develops at a slower rate than
the other types. Type IV is used primarily in large concrete structures, such as gravity dams, where the
temperature rise from the heat of hydration could damage the structure. Type IV cement will reach its
design strength in 90 days.
Type V. This concrete is sulfate-resistant and is used mainly where the concrete is subject to severe
sulfate action, such as when the soil or groundwater contacting the concrete has a high sulfate content.
Type V cement will reach its design strength in 60 days.
Other ASTM Cements
Separate ASTM specifications cover the following types of portland cements:
Air-entrained portland cement. Types IA, IIA, and IIIA correspond in composition to Types I, II, and III,
with the addition of small quantities of air-entrained materials interground with the clinker during
manufacturing. Air-entrained portland cements produce concrete that have improved resistance to freeze-
thaw action and to scaling caused by snow and ice removal chemicals. Such concrete contains extremely
small (as many as 300 billion per cubic yard), well-distributed, and completely separate air bubbles.
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