UFC 3-260-11FA
25 May 2005
interlock for load transfer. Aggregate interlock can be improved by the
angularity of aggregates and shorter joint spacing.
Keyway. Keyways have been used extensively to provide load transfer
along longitudinal joints. Because of a substantial amount of keyway
failure in pavements, keyways cannot be used on Army or Air Force
pavements, and only on Navy pavements 225 millimeters (mm) (9 in.)
or more in thickness.
Dowel Bars. Dowel bars are commonly used to provide load transfer
across expansion joints, butt construction joints, or contraction joints.
Thickened Edge. The pavement is thickened along the joint to reduce
pavement deflection (and stress) under load so that a load transfer
device, such as a dowel bar, across the joint is not needed.
Stabilized Base. Stabilized bases do not provide load transfer but
reduce pavement deflections. The Navy requires a stabilized base on
pavements thinner than 225 mm (9 in.) in lieu of load transfer.
3-6.10.3.2
Load Transfer Criteria
Construction Joints. Keyways are not allowed in Army or Air Force
pavements, but the Navy allows keyways on pavements thicker than
225 mm (9 in.). Butt joints can be used on Navy pavements less than
225 mm (9 in.) without load transfer on a stabilized base. Butt joints
can be used on all thicknesses of pavement with the use of dowel
bars. Thickened edge butt joints can be used on all thicknesses of
pavement without dowel bars.
Contraction Joints. Use aggregate interlock, except for the last three
joints at runway ends, which must be dowelled. Similar dowel
requirements should be included in the transverse contraction joints at
the end of other long paved areas, such as taxiways and aprons where
local experience indicates excessive joint opening may occur and/or
where the paved ends are unconfined. For the Navy, use Number 5
deformed tie bars in longitudinal contraction joints within 4.6 m (5 ft) of
a free edge of paved areas greater than 30 m (100 ft) wide.
Expansion Joints. Use dowels or thickened edge for all expansion
joints.
Thickened Edge. The pavement is thickened along the joint to reduce
pavement deflection under load so that a load transfer device across
the joint is not needed.
3-6.10.4
Sealant Types. Four types of joint sealants are used on military airfields.
Preformed
Field formed hot applied
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