UFC 3-270-04
15 March 2001
Hole diameters exceeding the bar diameter by 1/8 inch (3 millimeters) or less are recommended
when using epoxy mortar materials. Care must be exercised in epoxy grouting dowels or tie bars
to ensure complete coverage and support of the device. Grout retention devices that fit tightly
over the dowel or tie bar and effectively seal the hole should be used to prevent loss of grout or
epoxy. Smooth steel dowels are provided in concrete pavement slabs to transfer loads to
adjacent slabs and to help maintain the alignment of adjoining slabs. Dowels are placed in joints
that are intended to accommodate movement of the adjoining slabs. When using dowels, the end
that entends into the repair area should be painted and oiled to prevent bonding with the patch
material. Dowels used at expansion joints should be capped at one end, in addition to painting or
oiling, to permit further penetration of the dowels into the concrete when the joints close.
Deformed tie bars have surface ridges that provide a locking anchorage with surrounding
concrete. Tie bars are placed in joints that are not intended to have movement. Any dowels,
tiebars, or reinforcement must be clean and free of flaking rust.
4.8. Replacing Reinforcement. Successful performance of continuously reinforced concrete
pavements requires good load transfer across all transverse cracks and repair joints. Failure to
do so and to carry the longitudinal reinforcing steel through the repair will cause the repair and
the surrounding pavement to fail as the cracks begin to open. The longitudinal reinforcing is
generally carried through these repairs by careful removal of the old concrete to allow the
appropriate length of steel (lap length) from the existing pavement to extend into the repair area.
This steel is then tied, welded, or mechanically connected to additional reinforcing steel that
extends through the repair area. When replacing reinforcing in the patch area, the type of bars
should match the original in grade, quality, and number. The new bar should be placed on bar
supports to ensure proper position and cover, they should not extend closer than 2 inches
(152 millimeters) to the patch/slab interface. Tied splices should be lapped the proper length
(TM 5-825-3/AFM 88-6, Chap. 3) that provides full bar strength. Welded splices should be of the
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