T junction
From Free net encyclopedia
A T junction is a type of road junction with three arms where one (often minor) road connects to another (often major) road in a "T" shape. This is as opposed to a Y junction, which also has three arms but without this clear distinction of two arms forming one road and the third being a different road.
While some T junctions are controlled by traffic lights, most rely upon drivers to obey agreed rules. The vehicle travelling on the bar of the "T" typically has right-of-way; the vehicle approaching the "major" road must allow it to pass before joining the flow of traffic.
An experiment was done 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.