Designers are reaching a point where they can no longer hope to accommodate projected traffic demands with conventional freeway designs. The problems of not enough freeway capacity and not enough merging capacity are aggravated by severe unbalances of flow during peak hours. When the directional distribution of traffic on a multilane highway is greatly out of balance during peak hours the capacity of a given section can be appreciably increased by devoting more than half of the lanes to the predominant direction of flow. This principle of reverse-flow operation is grudgingly being applied to freeway design with limited success. This paper is a generalization of the reverse-flow freeway concept in that it suggests some interchange designs which enable ingress directly to and from the at-grade street system rather than the outside freeway roadways. In addition to preserving the increased capacity of the reversible freeway lanes, this innovation should double or triple the merging capacity at certain interchanges. A step- by-step procedure for utilizing this new type of reverse- flow facility is explained. The geometrics of the proposed interchanges are discussed in detail, complete with a plan- profile, typical section, and proposed signalization phasing plan. /author/.
Samenvatting