Editing Pothole (section)

== Formation ==
[[File:Factors leading to pothole failure by fatigue.png|thumb|Factors leading to pothole failure by fatigue in areas subject to freezing and thawing are: 1. Precipitation adds moisture to supporting soil structure. 2. [[Frost heaving]] can damage pavement. 3. Thawing can weaken soil structure. 4. Traffic can break the pavement.]]
According to the [[US Army Corps of Engineers]]'s [[Cold Regions Research and Engineering Laboratory]], pothole formation requires two factors to be present at the same time: water and traffic. Water weakens the soil beneath the pavement while traffic applies the loads that stress the pavement past the breaking point. Potholes form progressively from [[fatigue (material)|fatigue]] of the [[road surface]] which can lead to a precursor failure pattern known as [[Crocodile cracking|crocodile (or alligator) cracking]].<ref name = "croll">{{Cite journal
 | last = Croll
 | first = James G. A.
 | title = The role of thermal ratcheting in pavement failures
 | journal = Proceedings of the Institution of Civil Engineers - Transport
 | publisher = Proceedings of the Institution of Civil Engineers
 | series = Transport
 | volume = 162
 | issue = 3
 | edition = 3
 | date = January 2009
 | pages = 127–140
 | doi = 10.1680/tran.2009.162.3.127
 }}</ref> Eventually, chunks of pavement between the fatigue cracks gradually work loose, and may then be plucked or forced out of the surface by continued [[Axle load|wheel load]]s to create a pothole.<ref name = "Eaton"/>

In areas subject to freezing and thawing, frost heaving can damage a pavement and create openings for water to enter. In the [[spring (season)|spring]], thaw of pavements accelerates this process when the thawing of upper portions of the soil structure in a pavement cannot drain past still-frozen lower layers, thus saturating the supporting soil and weakening it.<ref name = "Eaton"/>

Potholes can grow to several feet in width, though they usually only develop to depths of a few inches. If they become large enough, damage to tires, wheels, and vehicle [[suspension (vehicle)|suspension]]s is liable to occur. Serious [[road accidents]] can occur as a direct result, especially on those roads where vehicle speeds are greater.<ref name = "Eaton">
{{Cite book
 | last1 = Eaton
 | first1 = Robert A.
 | last2 = Joubert
 | first2 = R. H.
 | last3 = Wright
 | first3 = E. A.
 | title = Pothole primer—A public administrator's guide to understanding and managing the pothole problem
 | publisher = US Army Corps of Engineers—Cold Regions Research & Engineering Laboratory
 | series = Special Report
 | volume = 81-21
 | date = December 1989
 | pages = 34
 | doi = 10.21236/ada107294
 | hdl = 11681/12121
 | url = http://www.idot.illinois.gov/Assets/uploads/files/Transportation-System/Manuals-Guides-&-Handbooks/T2/P009.pdf
 | s2cid = 106820435
}}</ref>

Potholes may result from four main causes:<ref name = "Eaton"/>
# Insufficient pavement thickness to support traffic during freeze/thaw periods without localized failures
# Insufficient drainage
# Failures at utility trenches and castings ([[manhole]] and drain casings)
# Pavement defects and cracks left unmaintained and unsealed so as to admit moisture and compromise the structural integrity of the pavement