Gravel road embankments in low-lying areas. Cellular confinement systems can be used to prevent the washboarding effect. The gravel used consists of varying amount of crushed stone, sand, and "fines". Fines are silt or clay particles smaller than , which can act as a binder. Crushed stone is used because gravel with fractured faces will stay in place better than rounded river pebbles. A good gravel for a gravel road will have a higher percentage of fines than gravel used as a subbase for a paved road. This often causes problems if a gravel road is paved without adding sand and gravel
Granular convection similar density, such as muesli mix. Under experimental conditions, granular convection of variously sized particles has been observed forming convection cells similar to fluid motion. The convection of granular flows is becoming a well-understood phenomenon. It may be counterintuitive to find that the largest and (presumably) heaviest particles rise to the top, but several explanations are possible: The phenomenon is related to Parrondo's paradox in as much as the Brazil nuts move to the top of the mixed nuts against the gravitational gradient when subjected to random shaking. Granular convection has been probed by the use of MRI where convection