Quadrant roadway intersection

The design is intended to improve traffic flow by reducing signal timing phases from four to two in the main intersection.

The design is intended for intersections where large artery routes meet in an area of dense development and high pedestrian volume.

[1][2] Proponents also point to a reduction in places where accidents could occur from vehicles potentially crossing paths, as well as a low development cost compared to roundabouts or the more complex single-point urban interchange designs.

[4] This type of junction is common in Germany, where it is called a "partial at-grade intersection" (German: Teilplangleicher Verkehrsknoten).

With circular ramps built on the southwest quadrant of two expressways, the Ohashi JCT was designed in a four-leveled manner.

A single-quadrant roadway intersection. Note how left turns are not available at the main intersection. This allows the signaling there to work with just two phases instead of four.

Left-turning traffic is directed away from the main intersection, as exemplified by green and blue traffic: Green traffic arrives from the south and wants to turn left/west. Blue traffic arrives from the east and want to turn left/south. Left-turning traffic from the remaining two directions not shown for clarity.
German one-quadrant interchange (or Verkehrsknoten teilplangleich )
Japanese quadrant interchange of Ohashi Junction in Tokyo . Circular ramps can be seen on the southwest quadrant at the intersection of Shibuya Route and Central Circular Route , Shuto Expressway .