TM 5-623
Figure B-29. High-severity edge cracking.
Figure B-30. High-severity edge cracking.
How to Measure:
Edge cracking is measured in linear feet.
Name of Distress:
Joint Reflection Cracking (from Longitudinal and Transverse PCC Slabs).
Description:
This distress occurs only on asphalt-surfaced pavements which have been laid over
a PCC slab. It does not include reflection cracks from any other type of base
(i.e., cement- or lime-stabilized); such cracks are listed as longitudinal cracks
and transverse cracks. Joint reflection cracks are mainly caused by the
thermal- or moisture-induced movement of the PCC slab beneath the AC
surface. This distress is not load-related; however, traffic loading may cause a
breakdown of the AC surface near the crack. If the pavement is fragmented
along a crack, the crack is said to be spalled. A knowledge of slab dimensions
beneath the AC surface will help to identify these distresses.
Severity Levels:
L-One of the following conditions exists (fig B-31):
Figure B-31. Low-severity joint reflection cracking.
1. Nonfilled crack width is less than X inch, or
2. Filled crack of any width (filler in satisfactory condition).
M-One of the following conditions exists (fig B-32):
B-11
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