UFC 3-270-03
15 March 2001
CHAPTER 4
PURPOSE OF CRACK AND SPALL REPAIR
4.1. Description. The primary purpose of sealing cracks and repairing spalls in Portland
Cement Concrete pavements on airfields is to reduce the costs associated with aircraft damage
due to FOD and to prolong the service life of the pavement to reduce the life-cycle costs for the
pavement structure. A considerable investment has been made in the construction of a concrete
surface and the vehicles that use these surfaces; therefore, costs decrease dramatically for every
additional year of pavement use that does not cause vehicle damage or require repeated
patching or full slab replacement. Routine periodic inspections and rapid repair of pavement
problems are essential for reducing life-cycle costs (References 1.3.1. and 1.3.2.). A properly
constructed and maintained pavement can last for many years.
4.2. Spalls. Spalling is generally caused by incompressible materials present in the joints and
cracks that prevent the necessary movement of the slab due to thermal fluctuations, thereby
causing breaks in the concrete adjacent to the joint or crack. Spalls may also be caused by
snowplows, over working, or popouts. Incompressible materials must be removed from the joint
or crack, the spalled area patched, and the joint sealant replaced. Additional repairs of previous
spall repairs due to failure of the material or poor repair practices are also common. If the spall
depth is greater than the depth of half the slab, full-depth patching is needed. Full-depth patching
will not be covered in this manual but is addressed in Reference 1.3.1. Cracking of slabs can be due
to load-related failure or environmental stress on the slab.
4.3. Objective. The objective of crack sealing and spall repair is to reduce FOD and prevent
moisture or incompressible material (rocks, sand, other pieces of concrete, etc.) from entering
into the crack or joint. Unsealed cracks will allow moisture to penetrate under the slab causing an
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