Partial cloverleaf interchange: Difference between revisions

Revision as of 08:09, 23 February 2025

Revision as of 08:10, 23 February 2025

Line 88:

[[File:Halfklaverbladaansluiting.png|thumb|upright|A parclo AB2 interchange or folded diamond]]

[[File:Parclo-AB3.svg|thumb|upright|A parclo AB3 interchange (hybrid).<br />Samples: The [[Laurensberg]] interchange in [[Aachen]], Germany {{coord|50.804072|n|6.075574|e}} and US 74/NC 51 interchange near Matthews, North Carolina {{coord|35.125862|n|80.705334|W}} ]]

Parclo designs with only two quadrants are commonly referred to as folded diamonds, due to their similarity with [[diamond interchange]]s. Sometimes the ramps in a folded diamond are actually local streets; surface roads upgraded to higher standards often do this to save money on land acquisition. This type of interchange long predates the parclo; the [[Merritt Parkway]] and [[Queen Elizabeth Way]], both built in the 1930s, used mainly folded diamonds and [[cloverleaf interchange|cloverleaves]]. Another example of this is [[Ontario Highway 401|Highway 401]]'s interchange with [[Highway 2 (Ontario)|Highway 2]] east of Tilbury (Exit 63): the ramps also have intersections fairly close to the freeway to allow traffic to continue on a rural country road (Jeannette's Creek Road / McKinlay Road) which formerly met Highway 2. One of the examples in Asia includes the [[Clark Freeport and Special Economic Zone|Clark]] South exit in [[Subic–Clark–Tarlac Expressway|SCTEX]], which is a two quadrantAB2 parclo interchange.

Depending on traffic and land needs, hybrid designs, such as the ''parclo AB'' and ''parclo A3'', can be created. A notable example of a parclo AB interchange includes the [[Ontario Highway 417|Highway 417]] and the [[Woodroffe Avenue]] interchange in [[Ottawa]]. Other variants, not describable using Ontario's system, eliminate one or more outside ramps, while leaving the loop ramps in those quadrants. In the United States, folded diamonds are frequently used in interchanges with roads that have a [[railroad]] line closely paralleling the surface street; entrance/exit ramps are not permitted to have [[level crossing]]s in modern American practice.<ref>{{cite web|author=Dan ''Dan the Man''|title=The Cloverleaf Interchange|url=http://whereroadsmeet.8k.com/article/clover.htm|access-date=2008-04-24|url-status=dead|archive-url=https://web.archive.org/web/20080514013630/http://www.whereroadsmeet.8k.com/article/clover.htm|archive-date=2008-05-14}}.</ref>