UFC 3-250-03
15 May 2001
CHAPTER 1
INTRODUCTION
1. PURPOSE. This manual provides guidance for the preparation of drawings and specifications for
road and airfield flexible pavements using asphalt cement materials. The term "asphalt" is used herein
instead of bituminous (a generic term for both asphalt and tar materials) because this is the material
most widely used in pavement construction. In current practice tar or coal-tar is used only in instances
where fuel resistance is required. This manual also provides useful information for design engineers,
laboratory personnel, and project managers concerning mix design, materials, production, and
placement of the various asphalt mixtures.
2. SCOPE. This manual prescribes materials, mix design procedures, and construction practices for
flexible pavements.
3.
REFERENCES. Appendix A contains a list of references used in this manual.
4. UNITS OF MEASUREMENT. The unit of measurement in this manual is the International System
of Units (SI). In some cases inch-pound (IP) measurements may be the governing critical values
because of applicable codes, accepted standards, industry practices, or other considerations where the
IP measurements govern, the IP values may be shown in parenthesis following a comparative SI value
or the IP value may be shown without a corresponding SI value.
5. EXPLANATION OF SPECIAL TERMS. Special terms used in this manual are explained in the
glossary.
6. BACKGROUND. Asphalt mixtures (hot- and cold-mix asphalt and other asphalt surfaces) provide a
resilient, relatively waterproof, load-distributing medium that protects the base course and underlying
pavement structure from the harmful effects of water and the abrasion of traffic. Wear, weathering, and
deterioration from aging all act on asphalt pavements, and therefore, maintenance of these pavements
is necessary for a long life. The flexibility of asphalt mixtures allows a pavement structure to adjust
slightly to consolidation of underlying layers or deformation due to load without affecting pavement
performance. Flexible pavements also allow stage construction and may use a wide range of
construction materials, often leading to substantial savings through the use of locally available materials.
Additional pavement courses can be placed on existing pavements to provide additional structural
strength as total loads or traffic intensity increase. The paving engineer must design and construct the
most economical pavement that will satisfy the objective of long pavement life.
7. SAFETY CONSIDERATIONS. The policy of the Departments of the Army and Air Force is to
construct pavements that will provide the maximum safety for traffic. A non-skid surface is essential,
and proper grade control is required to provide rapid removal of surface water to minimize the potential
for hydroplaning. All pavement surfaces should exhibit a sufficiently coarse texture to provide skid
resistance. Aggregate types known to have a history of polishing should be avoided because they are
probably the greatest cause of low skid resistance, especially in surface treatments and seal coats.
Construction techniques are important for surface treatments and seal coats to ensure good bond
between the asphalt and aggregate providing for satisfactory aggregate retention. Pavement surfacings
that do not include aggregate should not generally be applied in areas of high-speed traffic.
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