Traffic Control

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             The interchange allows non-stop, full access between two busy roads. Traffic merges and weaves, and does not have to stop unless the interchange becomes too congested. (The Full Cloverleaf, http://www.kurumi.com/roads/interchanges/cloverleaf.html) .
             Cloverleaf interchanges are built with loop ramps to accommodate left-turn movements of traffic and are designed with an overpass as well. The four-quadrant cloverleaf interchanges are built within large urban cities, where the daily traffic flow is voluminous. This type of interchange is also very efficient because it can be used for either freeway to freeway junctions or freeway to road junctions. Furthermore, unlike full cloverleaf interchanges, partial cloverleaf interchanges are those with loops in one, two or three quadrants. Partial cloverleaf interchanges have two entrance ramps and two exist ramps, and some of the variants of these interchanges have intersections with traffic lights. Variants of partial cloverleaf interchanges are used because, in some cases, the layout of the land creates an obstruction. Sometimes traffic is better served if drivers can turn one way instead of the other. .
             The simplest and perhaps the most common type of interchange is the Diamond interchange. The classic diamond is often the choice of design for lower-traffic interchanges without any specific restrictions, and is used when a lower capacity road crosses a higher capacity road. The diamond is functionally equivalent to the partial cloverleaf, with two entrance ramps and two exist ramps. The diamond is not suitable for heavy traffic on the surface street or ramps, or for any heavy left-turning traffic. This interchange is built with one-way diagonal ramps in each quadrant. The ramps function as a junction of the freeway and the surface street. On the diamond interchange, traffic lights can often be found installed at the two points where the ramps meet the surface street.