Linear Cracking

These cracks, which divide the slab into two or three pieces, usually are caused by a combination of repeated traffic loading, thermal gradient curling, and repeated moisture loading (slabs divided into four or more pieces are counted as divided slabs). Hairline cracks that are only a few feet long and do not extend across the entire slab are counted as shrinkage cracks.

For Nonreinforced Slabs:

Severity Description
Low Nonfilled cracks less than 1/2 in (13 mm) or filled cracks of any width with the filler in satisfactory condition. No faulting exists.
Medium One of the following conditions exists: non-filled crack with a width between 1/2 and 2 in (13 and 50 mm); nonfilled crack less than 2 in (50 mm) wide with faulting of less than 3/8 in (10 mm), or filled crack of any width with faulting greater than 3/8 in (<  10 mm).
High One of the following conditions exists: non-filled crack with a width greater than 2 in (50 mm), or filled or nonfilled crack of any width with faulting greater than 3/8 in (10 mm).

For Reinforced Slabs:

Severity Description
Low Nonfilled cracks between 1/8 and 1 in (3 and 25 mm) wide; filled crack of any width with the filler in satisfactory condition. No faulting exists.
Medium One of the following conditions exists: non-filled cracks with a width between 1 and 3 in (25 and 75 mm) and no faulting; nonfilled crack of any width less than 3 in (75 mm) with less than 3/8 in (10 mm) of faulting, or filled crack of any width with less than 3/8 in (10 mm) faulting.
High One of the following conditions exists: nonfilled crack greater than 3 in (75 mm) wide, or filled or nonfilled crack of any width with faulting greater than 3/8 in (10 mm).