A cloverleaf interchange is a two-level interchange in which left turns (in countries that drive on the right) are handled by loop roads (U. County Route 549 is a County highway in the US state of New Jersey. County Route 571, abbreviated CR 571, is a County highway in the U In the field of Road transport, an interchange is a road junction that typically Right-hand traffic and left-hand traffic mean regulations requiring all traffic to keep either to the left or the right side of the Road. S. : ramps, UK: slip roads). RAMP was an American soul / Jazz band from Cincinnati Ohio. RAMP has mistakenly been said to stand for " Roy Ayers In the field of Road transport, an interchange is a road junction that typically To go left (in right-hand traffic), vehicles first pass either over or under the other road, then turn right onto a one-way three-fourths loop ramp (270°) and merge onto the intersecting road.
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Overview
Cloverleaf interchanges, viewed from overhead or on maps, resemble the leaves of a four-leaf clover. In Botany, a leaf is an above-ground Plant organ specialized for Photosynthesis. For information on the song go to Four Leaf Clover (song The four-leaf clover is an uncommon variation of the common three-leaved Clover.
In the United States, cloverleaf interchanges existed long before the interstate system. The United States of America —commonly referred to as the The Dwight D Eisenhower National System of Interstate and Defense Highways, commonly called the Interstate Highway System (or simply the Interstate System) They were originally created for busier interchanges that the original diamond interchange system could not handle. A diamond interchange is a common type of Road junction. Diamond interchanges are used where a Freeway crosses a minor road Their chief advantage was that they were free-flowing and didn't require the use of such devices as traffic signals. The traffic light, also known as traffic signal, stop light, traffic lamp, stop-and-go lights, robot or semaphore, This not only made them a viable option for interchanges between freeways (where such devices are typically not an option), but they could also be used for very busy arterials where signals could present congestion problems. An arterial road is a moderate or high-capacity Road which is immediately below a Highway Level of service.
They were used for over 40 years as the US interstate system expanded rapidly. Large transport trucks that exceeded the usual 25 MPH (40 km/h) speed limit too frequently rolled over the side. This article is about the semi-truck For the North American use of the word see Pickup truck. (For the South African airport with IATA code "KMH" see Johan Pienaar Airport. For a discussion of the maximum speed possible in the universe see Speed of light and Special relativity. ("Overturned big-rig on the ramp to. truckcartransporterarp750pixjpg|thumb|right|A tractor with an auto-transport Semi-trailer. . . " was and remains a common traffic report on radio. Traffic on Roads may consist of Pedestrians ridden or herded Animals Vehicles Streetcars and other Conveyances either singly Radio is the transmission of signals by Modulation of electromagnetic waves with frequencies below those of visible Light. ) For this reason, cloverleaf interchanges have become a common point of traffic congestion at busy junctions.
At-grade Cloverleaf configurations with full four leafs and full outside slip ramps are extremely rare, though one is known to exist in Toms River, New Jersey. An at-grade intersection is a junction at which two or more transport axes cross at the same Level (or grade) The Township of Toms River is a large township in Ocean County, New Jersey, United States, and the [1] Any other intersections with merely one, two, or three leaf ramps with outer ramps would not be designated a "cloverleaf" and simply be referred to as a Jughandle intersection. A jughandle is a type of ramp or Slip road that changes the way traffic turns left (when driving on the right)
History
The cloverleaf was first patented in the United States by Arthur Hale, a civil engineer in Maryland, on February 29, 1916. A patent is a set of Exclusive rights granted by a State to an inventor or his assignee for a fixed period of time in exchange for a disclosure of an The United States of America —commonly referred to as the A civil engineer is a person who practices Civil engineering, one of the many engineering professions Leap years Although the modern calendar counts a year as 365 days a complete revolution around the sun takes approximately 365 days and 6 hours Year 1916 ( MCMXVI) was a Leap year starting on Saturday (link will display the full calendar of the Gregorian calendar (or a Leap year [2] Several cloverleafs were built in the late 1920s, and it is unclear which was first. The 1920s is sometimes referred to as the " Jazz Age " or the " Roaring Twenties " when speaking about the United States and Canada
A modified cloverleaf, with the adjacent ramps joined into a single two-way road, was planned in 1927 for the interchange between Lake Shore Drive (US 41) and Irving Park Road (ILL 19) in Chicago, Illinois, but it is not clear if this was built. Year 1927 ( MCMXXVII) was a Common year starting on Saturday (link will display full calendar of the Gregorian calendar. Lake Shore Drive (colloquially referred to as LSD or simply Lake Shore or The Drive) is a mostly Freeway -standard Expressway running US Route 41 is a north-south United States Highway that runs from the Upper Peninsula of Michigan to Miami Florida. Illinois Route 19 (abbreviated IL-19, or simply Illinois 19) is a major east-west arterial road in northeastern Illinois, United States. Chicago (ʃɪˈkɑːgoʊ is the largest City by population in the state of Illinois and the American Midwest of the United States.
The Woodbridge Cloverleaf was built at Route 25 and Route 4 (now US 1/9 and Route 35) in Woodbridge Township, New Jersey. Route 25 was a major State highway in New Jersey, United States prior to the 1953 renumbering, running from the Benjamin Franklin Bridge Route 4 is a State highway in Bergen County and Passaic County, New Jersey, United States, that is also known as the Mackay Highway See also US Route 1 in New Jersey, US Route 9 in New Jersey U Route 35 is a State highway along New Jersey 's Atlantic Ocean coast primarily traveling through the easternmost parts of Middlesex Monmouth and Ocean Woodbridge Township is a Township in Middlesex County, New Jersey, United States. It opened in 1929, and is currently planned for replacement with a 5-ramp partial cloverleaf interchange (parclo). Year 1929 ( MCMXXIX) was a Common year starting on Tuesday (link will display the full calendar of the Gregorian calendar. The parclo interchange (a Portmanteau of partial cloverleaf interchange) is a modification of a Cloverleaf interchange. This was designed by the Rudolph and Delano building firm from Philadelphia, and was modeled after a plan from Buenos Aires, Argentina. Philadelphia (ˌfɪləˈdɛlfiə Buenos Aires is the Capital and largest city of Argentina. It is geographically located on the southern shore of the Río de la Plata, on the southeastern For a topic outline on this subject see List of basic Argentina topics.
The first cloverleaf west of the Mississippi River opened on August 20, 1931 at Watson Road and Lindbergh Boulevard near St. Louis, Missouri as part of an upgrade of US 66. The Mississippi River is the second longest River in the United States, with a length of from its source in Lake Itasca in Minnesota to Events 636 - Battle of Yarmouk: Arab forces led by Khalid ibn al-Walid take control of Syria and Palestine Year 1931 ( MCMXXXI) was a Common year starting on Thursday (link will display full 1931 calendar of the Gregorian calendar. Lindbergh Boulevard named after the aviator Charles Lindbergh, is a section of U US Route 66 (also known as the Will Rogers Highway after the humorist, and colloquially known as the "Main Street of America" or the "Mother [3] This interchange, however, has since been replaced with a diamond interchange. A diamond interchange is a common type of Road junction. Diamond interchanges are used where a Freeway crosses a minor road
The cloverleaf was patented in Europe in Switzerland on October 15, 1928. Switzerland (English pronunciation; Schweiz Swiss German: Schwyz or Schwiiz Suisse Svizzera Svizra officially the Swiss Confederation Events 533 - Byzantine General Belisarius makes his formal entry into Carthage, having conquered it from the Year 1928 ( MCMXXVIII) was a Leap year starting on Sunday (link will display full calendar of the Gregorian calendar. The first cloverleaf in Europe opened on November 21, 1936 (but was partly closed until November 5, 1938) at Schkeuditzer Kreuz near Leipzig, Germany. Events 164 BC - Judas Maccabaeus, son of Mattathias of the Hasmonean family restores the Temple in Jerusalem. Year 1936 ( MCMXXXVI) was a Leap year starting on Wednesday (link will display the full calendar of the Gregorian calendar. Events 1499 - Publication of the Catholicon in Treguier ( Brittany) Year 1938 ( MCMXXXVIII) was a Common year starting on Saturday (link will display the full calendar of the Gregorian calendar. This sort of fix restores section edit linkpoints to where they belong Germany, officially the Federal Republic of Germany ( ˈbʊndəsʁepuˌbliːk ˈdɔʏtʃlant is a Country in Central Europe. This is now the interchange between the A 9 and A 14, and has a single flyover from the westbound A 14 to the southbound A 9. is an Autobahn in Germany, connecting Berlin and Munich. It served as one of three Transit autobahns toward West Berlin during the Exit list |-|colspan="3"|---- |-|colspan="3"|---- (later Schwerin-Mitte |-|colspan="3"|---- bridge or tunnel|-|colspan="3"|---- Kamener Kreuz was the first in continental Europe to open fully in 1937, at A 1 and A 2 near Dortmund Germany. The Kamener Kreuz is a Cloverleaf interchange in North Rhine-Westphalia Germany where the Autobahnen A1 and A2 meet Year 1937 ( MCMXXXVII) was a Common year starting on Friday (link will display the full calendar of the Gregorian calendar. is an Autobahn in Germany. It runs from Oldenburg in Holstein to Saarbrücken, a distance of 730km (456 miles but is incomplete between Cologne is an Autobahn in Germany that connects the Ruhr area in the west to Berlin in the east Dortmund (ˈdɔʁtmʊnt is a City in Germany, located in the Bundesland of North Rhine-Westphalia, in the Ruhr area. Germany, officially the Federal Republic of Germany ( ˈbʊndəsʁepuˌbliːk ˈdɔʏtʃlant is a Country in Central Europe.
Problems
A point of conflict is the merging of exiting and entering traffic in the same lane, known as weaving. In the field of Road transport, an interchange is a road junction that typically Most road authorities have since been implementing new interchange designs with more straight exit ramps that do not result in weaving. Design is used both as a Noun and a Verb. The term is often tied to the various Applied arts and Engineering (See design disciplines These interchanges include the diamond, parclo and Single-point urban (SPUI) interchanges when connecting to an arterial road, and the stack or cloverstack when connecting to another freeway or to a busy arterial where signals are still not desired. A diamond interchange is a common type of Road junction. Diamond interchanges are used where a Freeway crosses a minor road The parclo interchange (a Portmanteau of partial cloverleaf interchange) is a modification of a Cloverleaf interchange. A single-point urban interchange ( SPUI, ˈspuːi or /ˈspjuːi/ also called a single-point interchange ( SPI) or single-point diamond interchange An arterial road is a moderate or high-capacity Road which is immediately below a Highway Level of service. A stack interchange is a free-flowing junction between two or more roads that allows turning in all directions An arterial road is a moderate or high-capacity Road which is immediately below a Highway Level of service.
Not only is this true for new interchanges but it also holds when existing cloverleaf interchanges are upgraded. In Norfolk, Virginia, the interchange between U.S. 13 and U.S. 58 was originally a cloverleaf--it has since been converted to a SPUI. Norfolk is an Independent city in the Commonwealth of Virginia in the United States US Route 13 is a north-south US highway established in 1926 that runs for from the northeastern suburbs of Philadelphia, Pennsylvania US Route 58 is an east-west US Highway that runs for 508 miles (818 km from U A single-point urban interchange ( SPUI, ˈspuːi or /ˈspjuːi/ also called a single-point interchange ( SPI) or single-point diamond interchange And many cloverleaf interchanges on California freeways are being converted to parclos. California ( is a US state on the West Coast of the United States, along the Pacific Ocean. The parclo interchange (a Portmanteau of partial cloverleaf interchange) is a modification of a Cloverleaf interchange. In Hampton, Virginia, a cloverleaf interchange between Interstate 64 and U.S. Route 258 has been partially unwound into a partial stack interchange. Hampton is an Independent city in Virginia, and therefore not part of any Virginia county Interstate 64 (abbreviated I-64) is an Interstate Highway in the eastern United States. US Highway 258 is a spur of US Highway 58. It currently runs for 217 miles (349 km from Fort Monroe Virginia to Jacksonville North Carolina A stack interchange is a free-flowing junction between two or more roads that allows turning in all directions From now until 2010, four cloverleaf interchanges along I-64/US 40 in St. Louis, Missouri are scheduled to be replaced with SPUIs as part of a major highway renovation project. Interstate 64 (abbreviated I-64) is an Interstate Highway in the eastern United States. Missouri ( or) is a state in the Midwestern region of the United States bordered by Iowa, Illinois, Kentucky, Tennessee A single-point urban interchange ( SPUI, ˈspuːi or /ˈspjuːi/ also called a single-point interchange ( SPI) or single-point diamond interchange
A compromise is to add a collector/distributor road next to the freeway; this doesn't eliminate weaving but moves it off the main lanes of the freeway. A collector/distributor road, often abbreviated as C/D road, is a one-way road next to a Freeway that is used for some or all of the ramps that would otherwise merge An example of this is the State Highway 23/I-43 interchange in Sheboygan, Wisconsin, where the exit/entrance roads on and off Highway 23 is two lanes next to the main I-43 freeway on the north and southbound sides of the road. State Trunk Highway 23 (often called Highway 23, STH 23 or WIS 23) is a state highway in the U Interstate 43 (I-43 is an intrastate Interstate highway located entirely within the state of Wisconsin. Sheboygan is a city in and the County seat of Sheboygan County, Wisconsin, United States.
A few cloverleaf interchanges in California have been rebuilt to eliminate weaving on the freeway while keeping all eight loop ramps, by adding bridges. California ( is a US state on the West Coast of the United States, along the Pacific Ocean.
Several cloverleafs have been eliminated by adding traffic lights on the non-freeway route. The traffic light, also known as traffic signal, stop light, traffic lamp, stop-and-go lights, robot or semaphore, Sometimes, this is even done at the intersection of two freeways, particularly when one freeway terminates at an interchange with another. An example of this is in Lakewood, Washington, at the interchange between Interstate 5 and State Route 512. Lakewood is a city in Pierce County, Washington, United States. Interstate 5 in Washington (I-5 is a highway in the US state of Washington that extends from its border with Oregon to its border with Canada State Route 512 ( SR 512) is a state highway in the US state of Washington, originating at Interstate 5 in Lakewood A visible ramp stub shows that one of the four leaves was removed; thus eliminating an unsafe weave on I-5. An unused highway may reference a Highway or highway ramp that was partially or fully constructed but was unused or later closed In the future, the traffic signal will be replaced by a 2 lane flyover, completing the freeway to freeway interchange once again. [1]
Cloverleafs also occupy much more land than any other kind of interchange (with the possible exception of stack interchanges). A stack interchange is a free-flowing junction between two or more roads that allows turning in all directions
The cloverleaf interchange was not implemented in great numbers in the United Kingdom, owing to these design issues. The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom, the UK or Britain,is a Sovereign state located There were originally three, one in Redditch and two in Livingston. Redditch is a Town and local government district in north-east Worcestershire, England. One of the Livingston examples was remodeled in the mid 2000s as part of a public transport project. The major junction of the M11 and A14 at the Girton interchange near the outskirts of Cambridge consists of two cloverleaf loops, making essentially a 'half' cloverleaf interchange. This page is about the M11 motorway in England For the M11 motorway in the Republic of Ireland see N11 road. The city of Cambridge (ˈkeɪmbrɪdʒ is a university town and the administrative centre of the county of Cambridgeshire, England This junction is prone to heavy traffic congestion at peak times, chiefly due to the requirement for westbound A14 traffic to exit the main dual carriageway, traverse one of the cloverleaf loops at slow speeds, then engage in weaving with traffic exiting the M11, in order to continue westward along the A14. A dual carriageway or divided highway is a road or Highway in which the two directions of traffic are separated by a central barrier or strip of land known as a
See also
- Jughandle, which can resemble the loop ramp of a cloverleaf with no bridge
- Cloverstack interchanges, a relative to the cloverleaf, hybridized with a stack interchange
References
External links
- Map of the Woodbridge, NJ Cloverleaf
- Map of the Toms River, NJ At Grade Cloverleaf
- UK-based discussion on cloverleaf interchanges