Double Crossover Merging Interchange

A double crossover merging interchange (DCMI) is a new type of interchange. The lane configuration allows for high capacity free-flow traffic without the need for costly elevated "flyover" roadway bridges, and uses less lane area and structures than an interchange with large radius flyover(s). The DCMI employs several of the design techniques of a newer alternative interchange referred to as a diverging diamond (or double crossover diamond) interchange. The double crossover merging interchange also has similarities to a standard diamond interchange and to a stack interchange.
The double crossover merging interchange has several distinct design features that differentiate it from a diverging diamond interchange. Utilizing a standard main bridge with two smaller underpass type bridges on either side of the main bridge, the double crossover merging interchange lets vehicles cross over conflicting traffic streams while removing weaving maneuvers. This configuration produces an interchange with merging maneuvers. By placing two smaller bridges (grade separation) on either side of the main bridge, the traffic signals can be eliminated. Additionally, off-ramp traffic can be crossed over on the same smaller side bridges used by the main traffic patterns. Hence, this removes conflicts that would take place with an at-grade traffic signal. The key feature of this type of design is not only the elimination of the conflicts that occur at-grade, but also allowing the off-ramp traffic to cross over without the need for lane changes or weaving within the interchange.
The double crossover merging interchange introduces a number of new mechanisms to a while producing a free-flow traffic environment interchange.
It is not known whether any such interchanges have been constructed.
Advantages
* No weaving sections
* Provides free-flow operations
* Reduced vehicle emissions (no idling vehicles)
* No right-angle crossing conflicts
* No delay incurred due to traffic signals
* Less costly to construct than a full free-flow interchange with flyover roadway bridges
Disadvantages
* May be more costly than a standard diamond or diverging diamond interchange to construct

Main Menu

See Also

Main Menu