Inspection Guidelines
Settlement or Faulting
Settlement or faulting is a difference of elevation at a joint or crack caused by upheaval or consolidation. Severity levels are defined by the difference in elevation across the fault and the associated decrease in ride quality and safety as severity increases.
How to Count
In counting settlement, a fault between two slabs is counted as one slab. A straightedge or level should be used to aid in measuring the difference in elevation between the two slabs.
| Severity | Distress Example | Description |
|---|---|---|
| Low |  | Runways/Taxiways: < 1/4 inch (< 6 mm) Aprons: 1/8 – 1/2 inch (3 – 13 mm) |
| Medium |  | Runways/Taxiways: 1/4 – 1/2 inch (6 – 13 mm) Aprons: 1/2 – 1 inch (13 – 25 mm) |
| High |  | Runways/Taxiways: > 1/2 inch (> 13 mm) Aprons: > 1 inch (> 25 mm) |