Three-way junction

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Three way junction at Dragons Green - geograph.org.uk - 1578998 Three way junction at Dragons Green - geograph.org.uk - 1578998.jpg
Three way junction at Dragons Green - geograph.org.uk - 1578998

A three-way junction (or three-way intersection) is a type of road intersection with three arms. A Y junction (or Y intersection) generally has three arms of equal size. A T junction (or T intersection) also has three arms, but one of the arms is generally a minor road connecting to a larger road.

Contents

Right-of-way

Some T junctions are controlled by traffic lights, but others rely upon drivers to obey right-of-way rules, which vary from place to place. For example, in some jurisdictions, vehicles on the right always have the right-of-way (even at T junctions), [1] while in other jurisdictions, vehicles travelling on the "through" road of a T junction have the right-of-way, meaning that vehicles approaching the "major" road must allow through traffic to pass before joining the flow of traffic.

In the People's Republic of China, going straight on red when approaching a T junction on the main road with the intersecting road on the left was permitted until the Road Traffic Safety Law of the People's Republic of China took effect on 1 May 2004.

In Taiwan (administered by the Republic of China), when at least two vehicles reach a T intersection without a working traffic light, the vehicle on the side road is to yield to any other vehicle straight on the main road. If two vehicles want to turn left, the vehicle on the left is to yield. [2]

Turns

When one road at a 3-way junction has a higher traffic volume than the other (and particularly when the roads are perpendicular to each other), turns are characterized as "right-in", "right-out", "left-in" and "left-out". A turn "in" represents a turn from the major road into the minor road. A turn "out" represents a turn out of the minor road onto the major road. A 3-way junction allowing all four of these turns is characterized as "full-movement". These terms also apply to turns between roads and driveways. [3] [4]

Variations

An experiment was done[ by whom? ][ when? ] in Illinois, United States to allow going straight on red (like a right turn on red) when approaching a T junction on the main road, with the intersecting road on the left. It was a failure. However, at some T junctions where the main road includes at least two lanes on the side away from the intersecting road, the farthest (rightmost, in areas where traffic drives to the right) lane is given the right of way to proceed straight through the intersection at all times, denoted by a "green arrow" signal if a traffic light is installed at the intersection.

In such cases, often that lane is also specially delimited with pavement markings or other lane separation devices, to keep left-turning traffic on the intersecting road from colliding with traffic proceeding through the intersection on the main road. There are now safer variations of this, called continuous green-T (or seagull) intersections , that have a left turn lane off the main road either channelized or otherwise separated from traffic going straight, which allows for a traffic signal on only one side of the road. [5]

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Traffic on roads consists of road users including pedestrians, ridden or herded animals, vehicles, streetcars, buses and other conveyances, either singly or together, while using the public way for purposes of travel.

Roundabout Traffic intersection

A roundabout is a type of circular intersection or junction in which road traffic is permitted to flow in one direction around a central island, and priority is typically given to traffic already in the junction.

Intersection (road) A road junction where two or more roads either meet or cross at grade

An intersection is an at-grade junction where two or more roads or streets meet or cross. Intersections may be classified by number of road segments, traffic controls or lane design. In general, there are two types of intersections including signalized and unsignalized intersections.

Traffic light Signaling device to control competing flows of traffic

Traffic lights, traffic signals, stoplights or robots are signalling devices positioned at road intersections, pedestrian crossings, and other locations to control flows of traffic.

Michigan left Type of intersection

A Michigan left is an at-grade intersection design that replaces each left turn at an intersection between a (major) divided roadway and a secondary (minor) roadway with the combination of a right turn followed by a U-turn, or a U-turn followed by a right turn, depending on the situation.

Diamond interchange

A diamond interchange is a common type of road junction, used where a controlled-access highway crosses a minor road.

Jughandle

A jughandle is a type of ramp or slip road that changes the way traffic turns left at an at-grade intersection. Instead of a standard left turn being made from the left lane, left-turning traffic uses a ramp on the right side of the road. In a standard forward jughandle or near-side jughandle, the ramp leaves before the intersection, and left-turning traffic turns left off of it rather than the through road. Right turns are also made using the jughandle.

Superstreet

A superstreet, also known as a restricted crossing U-turn (RCUT), J-turn, or reduced conflict intersection (RCI), is a type of road intersection that is a variation of the Michigan left. In this configuration, in contrast to the Michigan left, traffic on the minor road is not permitted to proceed straight across the major road or highway. Drivers on the minor road wishing to turn left or go straight must turn right onto the major road, then, a short distance away, queue (wait) into a designated U-turn lane in the median. When traffic clears, they complete the U-turn and then either go straight or make a right turn when they intersect the other half of the minor road.

Interchange (road) Road junction, typically using grade separation

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A junction is where two or more roads meet.

Turn on red

A turn on red is a principle of law permitting vehicles at a traffic light showing a red signal to turn into the direction of traffic nearer to them when the way is clear, without having to wait for a green signal. It is intended to allow traffic to resume moving, with minimal risk provided that proper caution is observed.

Traffic-light signalling and operation

The use of traffic lights to control the movement of traffic differs regionally and internationally in certain respects. This article describes some of these non-universal features. Note that the color phase commonly known as "yellow" is often referred to, especially in official usage, as "amber"; for consistency this article uses "yellow" throughout.

All-way stop

An all-way stop – also known as a four-way stop – is a traffic management system which requires vehicles on all the approaches to a road intersection to stop at the intersection before proceeding through it. Designed for use at low traffic-volume locations, the arrangement is common in the United States, Canada, South Africa, Liberia, and Mexico, as well as in a number of, usually rural, locations in Australia where visibility on the junction approaches is particularly poor. The stop signs at such intersections may be supplemented with additional plates stating the number of approaches.

Road signs in Thailand

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The road signs in Poland follow the Vienna Convention on Road Signs and Signals and, therefore, are more or less identical to those in other European countries. Warning signs have yellow background rather than the more common black-on-white design, and therefore similar to the Road signs in Greece.

Road signs and symbols used in Germany are prescribed under the Straßenverkehrs-Ordnung (StVO) and the Katalog der Verkehrszeichen (VzKat).

A wide variety of road signs are displayed in the People's Republic of China.

Glossary of road transport terms Wikipedia glossary

Terminology related to road transport—the transport of passengers or goods on paved routes between places—is diverse, with variation between dialects of English. There may also be regional differences within a single country, and some terms differ based on the side of the road traffic drives on. This glossary is an alphabetical listing of road transport terms.

Road signs in Cambodia

Road signs in Cambodia are standardized road signs similar to those used in other nations but with certain differences.

Road signs in the Philippines Wikimedia list article

Road signs in the Philippines are regulated and standardized by the Department of Public Works and Highways. Most of the signs reflects minor influences from American and Australian signage, but keeps close to the Vienna Convention as an original signatory.

References

  1. SGI. "SGI - Driver's Handbook - Right of way".
  2. Clause 2 of Section 1 of Article 102 of the Road Traffic Security Rules (s:zh:道路交通安全規則)
  3. Staff. "Technical Summary (FHWA-SA-10-002)". Access Management in the Vicinity of Intersections. Federal Highway Administration . Retrieved August 31, 2012.
  4. Joe G. Bared (January–February 2005). "Improving Signalized Intersections, Publication Number: FHWA-HRT-05-003". Public Roads. Federal Highway Administration. 68 (4). Retrieved August 31, 2012.
  5. An Applied Technology and Traffic Analysis Program ( "Archived copy". Archived from the original on 2012-02-08. Retrieved 2007-10-12.CS1 maint: archived copy as title (link))