DEPARTMENT OF THE ARMY
U.S. Army Corps of Engineers
Washington, D.C. 20314-1000
29 January 1988
Engineering and Design
THICKNESS DESIGN OF ROLLER-COMPACTED CONCRETE PAVEMENTS FOR
AIRFIELDS, ROADS, STREETS, AND PARKING AREAS
1. Purpose. This letter describes the procedures used to design the
thickness of roller-compacted concrete pavements (RCCP) for airfields,
roads, streets, and open storage areas.
This letter applies to all HQUSACE/OCE elements and all
field operating activities (FOA) having military construction and civil
works design responsibility.
a. Roller-compacted concrete pavement is a construction method using a
cement concrete mixture that is placed with an asphalt
concrete paving machine and compacted with vibratory and rubber-tired
rollers. For additional details on properties of roller compacted concrete
for pavements, see TM 5-822-7, appendix D.
b. A major difference exists in the assumptions of load transfer at
joints made for conventional concrete pavements and RCCP, which directly
effects the design stress and the thickness of the pavement. RCCP has
typically been allowed to crack naturally, and the spacings between these
cracks are usually irregular, ranging from 40 to 70 feet apart (although
spacings much greater and much lower than these have been reported).
Consequently, the width of the crack opening will`be greater and the load
transfer developed from aggregate interlock at the cracks will be highly
variable, if not totally lost. Limited tests at Ft. Hood, TX and Ft.
Stewart, GA, have revealed average load transfer at transverse contraction
cracks of 18.6 percent (standard deviation of 6.7 percent) and 16.7 percent
(standard deviation of 5.9 percent), respectively. Tests on longitudinal
and transverse construction joints revealed even less load transfer.
Therefore, the assumption of 25 percent load transfer at joints in open
storage areas and airfields constructed of plain concrete may not be valid
for RCCP thickness design. Therefore, the approach is to base the
thickness design of RCCP on no load transfer at the joints, i.e., assuming
all joints/cracks to be a free edge condition.