Permanent deformation along the wheel paths, showing as long depressions, often with slight humps beside them. Mix rutting comes from an asphalt layer flowing under hot-weather traffic: too much binder, too few voids, soft binder or rounded aggregate. Structural rutting comes from deformation in the base or subgrade and shows as a wider, shallower dip. Ruts deeper than about half an inch hold water and raise the risk of hydroplaning.
Rutting's an inch deep at the truck scale, core it and see if it's the surface mix flowing or the base sinking.
Also heard as
- ruts
- wheel path rutting
- permanent deformation
Related terms
Hamburg wheel-tracking test
A lab test that rolls a loaded steel wheel over submerged mix samples to measure rutting and moisture damage.
Shoving
Localized bulging and sliding of the asphalt surface where traffic brakes, turns or accelerates.
MSCR
Multiple stress creep recovery: a high-temperature binder test measuring how much of a deformation the binder recovers.
Fatigue cracking
Interconnected cracks in the wheel paths caused by repeated bending under traffic, known as alligator cracking.