UFC 3-270-04
15 March 2001
11.2. Surface Preparation. Prior to starting the work, it is necessary to determine the condition
of the surface to be treated and to determine what surface preparation is required. Two surface
conditions must be met if repairs are to be successful:
11.2.1. The concrete surface must be strong and sound, and all loose deteriorated and unsound
material should be removed. Patching over delaminated areas should not be done. The
delaminations can be repaired by epoxy injection or similar techniques, but long-term durability of
such patches over repaired delaminations is likely to be impaired. In spalled areas, concrete
removal may require the use of chipping hammers, scarifiers, sand blasters, high-pressure water
blasters, or a combination of these.
11.2.2. The concrete surface must be dry and clean (free from laitance, dirt, oil, grease, paints,
and curing compounds). Moisture on the concrete surface should be removed, unless the
adhesion of the PC material to be used is not affected by moisture. Dust and debris may be
removed by blowing with clean, dry, compressed air. Mechanical abrasion may also be
necessary to achieve the desired bond between the PC and the concrete surface. Any exposed
reinforcing steel in the repair area should also be cleaned by mechanical abrasion prior to the
application of PC patching material. Mechanical abrasion that results in damage to the
reinforcing steel should not be used.
11.3. Polymer Concrete Patching Materials. PC patching materials are particularly useful for
the repair of portland cement pavements where traffic conditions allow closing of the repair area
for only a few hours. The fast-curing, high-strength characteristics of PC patching materials are
well suited on these applications. PC is not limited to that usage, however, and can be
formulated for a wide variety of applicaton needs; thus, care must be exercised in selecting the
right material for the job it is to perform. Some of the most widely used monomers for PC
patching materials include methracylate (MMA), styrene (STY), unsaturated polyester resins
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