An Evaluation of New Jersey Jug-Handle Intersection (NJJI) with and without Pre-Signals

Conventional treatment of left-turn at major arterial intersections is often found to be the major cause of poor arterial operations, especially under a heavy volume condition. New Jersey Jug-handle Intersection (NJJI), an unconventional intersection scheme, eliminates direct left turn and has been in place on NJDOT heavy-volume arterial roadways for quite a long time. The NJJI scheme separates left turn vehicles prior to or after crossing the intersection via a right side jug-handle (forward or reverse) ramp and then allow them to make turn onto cross-street via ramp terminus separated from the main intersection. By introducing jug-handle ramps at all four approaches of a four-legged intersection, four identical ramp termini can be constructed. These ramp termini can be signalized along with the main intersection and each of them can be operated on a two-phase signal. CORSIM, a micro-simulation model, has been utilized to evaluate and compare the operational performance of a forward ramp NJJI scheme (with and without signals at the ramp termini) with a conventional intersection (CI) scheme. The simulation study reveals that the NJJI scheme with pre-signals significantly improves traffic operations while increasing the intersection capacity. Other benefits of the NJJI scheme include reduction of vehicle stop time, fuel consumption and emission level.