1. ARTERIAL INTERCHANGE Four exit ramp, split level (SPUI)
With offset intersections
SRF Consulting Group – May 2006

2. VISSIM SCREEN SHOTS
Volumes used in simulation – year 2030 pm peak hour, for Mn Hwy 55 at Vicksburg Lane in Plymouth
WB Mainline (underpass) 2910
Left turns – 120
Right turns – 415
Mainline through – 2375
EB Mainline (underpass) 1795
Left turns – 245
Right turns – 225
Mainline through – 1325
NB Cross street (over crossing) 1510
Left turns – 480
Right turns – 120
Throughs – 910
NB Cross street (over crossing) 1020
Left turns – 280
Right turns – 320
Throughs – 420
Represents junction of principle arterial (55,000 ADT) with minor arterial (25,000)

3. Two signal controlled intersections
Signals on each level to handle left turns from ramps. Right turns have extended acceleration lanes to enter mainline and Yield control to enter cross street. Lower volume left turns from each roadway have complex alignment to create single intersection of opposing lefts while retaining a rectangular bridge shape.

5. Underpass
Cross street follows a ridge. Mainline is lowered under intersection with 17 feet of vertical clearance.

6. FOUR EXIT RAMP SPLIT LEVEL SINGLE POINT (offset intersections)
INTERSECTION DETAILS
Alternative design has separate “conventional exit ramp intersections, but uses one signal controller with “split” phasing for the exit ramp greens, less capacity, but narrower bridge.
Offset single intersection allows for exit ramp lefts to be made concurrently.