30 June 2001
CONTINUOUSLY REINFORCED CONCRETE PAVEMENT DESIGN
1. BASIS OF DESIGN. A continuously reinforced concrete pavement is one in which the reinforcing
steel is carried continuously, in both the longitudinal (direction of paving) and transverse (normal to
direction of paving) directions, between terminal points. The terminal points may be either the
longitudinal construction joints or ends of the pavement, junctures with other pavements or structures,
etc. No joints are required between the terminal points; instead, the pavement is permitted to crack.
The crack spacing will vary and be dependent upon the percent of reinforcing steel used, interface
conditions between the pavement and foundation, and environmental conditions during the early life of
the pavement. A transverse crack spacing ranging from 1.5 to 2.5 meters (5 to 8 feet) is desirable;
however, experience has shown that even for the most carefully designed system, the crack spacing will
vary from as little as 0.6 meters (2 feet) to as much as 3.5 meters (12 feet). The reinforcing steel
provides continuity across the nonload-induced cracks, holding them tightly closed and providing good
transfer of load. Considerable trouble has been encountered from underdesigned continuously
reinforced concrete highway pavements. Consequently, the current trend and the approach adopted
here is to make continuously reinforced concrete pavements the same thickness as plain concrete. The
steel is assumed to only handle nonload-related stresses and any structural contribution to resisting
loads is ignored. When properly designed and constructed, continuously reinforced concrete pavements
provide very smooth, low-maintenance pavements. Experience has shown that continuously reinforced
concrete pavements perform satisfactorily until the level of cracking reaches the point where punchout of
the concrete between the reinforcing steel bars is imminent. The design procedure has been developed
primarily from the results of continuously reinforced concrete pavement performance on highways since
there has been only limited experience with airfield pavements.
2. USE FOR CONTINUOUSLY REINFORCED CONCRETE PAVEMENTS. Continuously reinforced
concrete pavements are applicable for any airfield pavement, but they have received very limited usage
for airfield pavement construction. Therefore, long-time performance history is minimal. Because of this,
its use will require approval of the Commander, U.S. Army Corps of Engineers (CEMP-ET), the
appropriate Air Force Major Command, or the Naval Facilities Engineering Command. The use of
continuously reinforced concrete pavement should be based upon the economics involved.
3. FOUNDATION REQUIREMENTS AND EVALUATION. Subgrade compaction and evaluation for a
continuously reinforced concrete pavement shall be as described for plain concrete pavements. If
economically feasible, the subgrade and/or base course may be modified or stabilized. Stabilized
materials must achieve the strength and durability requirements specified in
TM 5-822-14/AFJMAN 32-1019.
4. THICKNESS DESIGN. The required thickness of a continuously reinforced concrete pavement is
determined using the same procedures as for plain concrete pavement and will be the same thickness
as plain concrete pavement. Although continuously reinforced concrete pavement contains steel in
addition to being the same thickness as plain concrete pavement, the advantage of using it is that
contraction joints are eliminated.