TM 5-826-6/AFR 93-5
Figure A-101. Popouts.
(3) Counting procedure. The density of the distress must be measured. If there is any doubt about the average
being greater than three popouts per square yard, at least three random 1-square-yard areas should be checked. When
the average is greater than this density, the slab is counted.
y. Pumping, distress 69.
(1) Description. Pumping is the ejection of material by water through joints or cracks caused by deflection of
the slab under passing loads. As the water is ejected, it carries particles of gravel, sand, clay, or silt resulting in a
progressive loss of pavement support. Surface staining and base or subgrade material on the pavement close to joints or
cracks are evidence of pumping. Pumping near joints indicates poor joint sealer and loss of support, which will lead to
cracking under repeated loads.
(2) Severity levels. No degrees of severity are defined. It is sufficient to indicate that pumping exists (figs. A-
102 through A-105). Fine material on surface that has been pumped out causing corner break, stains on pavement, and
close-up of fine materials collecting in a joint are show in figures A-102 through A-105, respectively.
Figure A-102. Pumping.
A-58
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