Spalling

Description

Cracking, breaking or chipping of joint/crack edges. Usually occurs within about 0.6 m (2 ft.) of joint/crack edge.

Problem

Loose debris on the pavement, roughness, generally an indicator of advanced joint/crack deterioration

Possible Causes

Possible causes are (AASHTO, 1993¹):

• Excessive stresses at the joint/crack caused by infiltration of incompressible materials and subsequent expansion (can also cause blowups).
• Disintegration of the PCC from freeze-thaw action or "D" cracking.
• Weak PCC at a joint caused by inadequate consolidation during construction. This can sometimes occur at a construction joint if (1) low quality PCC is used to fill in the last bit of slab volume or (2) dowels are improperly inserted.
• Misalignment or corroded dowel.
• Heavy traffic loading.

Repair

Spalling less than 75 mm (3 inches) from the crack face can generally be repaired with a partial-depth patch. Spalling greater than about 75 mm (3 inches) from the crack face may indicated possible spalling at the joint bottom and should be repaired with a full-depth patch.

@misc{pavint-spalling,
  author = {{Pavement Interactive}},
  title = {Spalling},
  year = {2018},
  publisher = {HeadLight},
  howpublished = {\url{https://pavementinteractive.org/reference-desk/pavement-management/pavement-distresses/spalling/}},
  note = {Accessed [date]}
}