AI.6.A. Intersection Type References Intersection Control Type Mode Accommodations Reference Material Recommended Analysis Tool Intersection Name Illustration1 Description Vehicles Pedestrians Bicycles Two-way stop-control Conventional intersection control type in which the minor street approaches are stop-controlled and major street movements do not encounter any traffic control devices. Through- and movements on the major street approaches are movements, while left-turning movements are permissive. All minor street approaches are stop-controlled. Pedestrians crossing the minor street approaches have right-of-way and are crossing at a location; however, the lack of signalization does not provide any protected pedestrian movement across the major street. Ride on street in travel lane or bicycle lane (if available), unless multi-use path is present UIIG HCS, Synchro All-way Conventional intersection control type in which every approach is stop-controlled. All vehicles are required to stop before proceeding through the intersection. All pedestrian crossings are located at the same place as stop signs Ride on street in travel lane or bicycle lane (if available), unless multi-use path is present. UIIG HCS, Synchro Signalized Control Conventional intersection control type in which each approach is controlled by a traffic signal. Vehicular movements on each approach are controlled through protected, permissive, or prohibited lights on the traffic signal. Pedestrian phases can be built into the signal timing to allow for permissive pedestrian crossings at the designated crosswalks. Accessible pedestrian signals and pushbuttons can be utilized. Ride on street in travel lane or bicycle lane (if available), unless multi-use path is present. Signalized Intersection Guide, 2nd Edition HCS, Synchro
Roundabout A subset of circular intersections that feature yield control of all entering vehicles, channelized approaches, and horizontal curvature and roadway elements to induce desirable vehicle speeds. Vehicles approaching the intersection must yield to vehicles circulating within the circulatory roadway. Pedestrian crossings are located only across the legs of the roundabout, typically separated from the circulatory roadway by at least one vehicle length. Bicyclists may ride in the roadway with vehicles or transition to paths via bicycle ramps (if present). Bike lanes should not be used at roundabouts NCHRP 672 HCS, SIDRA with US HCM Model for designs not supported by HCS Median (MUT) An intersection treatment that eliminates direct at signalized intersections from major and minor approaches and replaces them with u-turns on the major street Drivers desiring to turn left from the major road onto an intersecting cross street must first travel through the signal-controlled intersection and then execute a U turn at the median opening downstream of the intersection. These drivers then can turn right at the cross street. For drivers on the side street desiring to turn left onto the major road, they must first turn right at the signal controlled intersection and then execute a U turn at the downstream median opening and proceed back through the signalized intersection. Larger clearance intervals are required for the side street signal phase, and wider medians are often used to accommodate Pedestrian crossings are often Ride on street in travel lane or bicycle lane (if available), unless multi-use path is present. Design techniques for direct left turns are available CAP-X (planning level) Synchro, SimTraffic VISSIM or similar microsimulation software
Signalized Restricted Crossing (RCUT), or Superstreet An intersection design that restricts left-turn and through movements from side street approaches as permitted in conventional designs. Left-turns and through movements from the minor street are required to turn right onto the main road and then make a U-turn maneuver at a one-way, signalized median opening 400 to 1,000 feet after the intersection. The major street effectively operates as a pair of one-way streets because no movement ever crosses both directions of the major street at once. Pedestrian crossings of the major road at the RCUT intersection are usually accommodated on one diagonal “Z” path from one corner to the opposite corner, and each crossing is signalized. Ride on street in travel lane or bicycle lane (if available), unless multi-use path is present. Side street through and left turn movements can use pedestrian crossings to avoid use of U-turn movements CAP-X (planning level) Synchro, SimTraffic VISSIM or similar microsimulation software Unsignalized Restricted Crossing (RCUT), or J-Turn Left-turns and through movements from the minor street are required to turn right onto the main road and then make a U-turn maneuver at a one-way, stop-controlled median opening 400 to 1,000 feet after the intersection. Unsignalized RCUTs are usually located in rural areas and do not have pedestrian facilities. Unsignalized RCUTs are usually located in rural areas and do not have bicycle facilities. Direct crossings from minor street to minor street can be facilitated with a cut-through in the median island.
Continuous Green Tee A continuous green tee intersection is a signalized 3-leg intersection that features raised channelization that separates the “top” through movement from the other movements of the intersection, enabling the top through movement to operate unsignalized with no conflicting movement. Minor street left-turns are channelized, allowing a continuous green signal to be displayed to one of the mainline through movements. Permissive pedestrian crossings are provided across the minor street at the signal. Due to the continuous flowing nature of through movements on one of the major approaches, pedestrian movements across the mainline should be accommodated at an adjacent intersection or via a mid-block crossing, as appropriate. Ride on street in travel lane or bicycle lane (if available), unless multi-use path is present. CAP-X (planning level) Synchro, SimTraffic VISSIM or similar microsimulation software Quadrant Roadway A quadrant roadway intersection is intended to eliminate all direct left-turn movements from the main intersection by them to turns to and from a connector roadway located in one quadrant. Left-turn movements are rerouted to use a connector roadway (i.e., the quadrant). All at the main intersection are prohibited, allowing for two-phase signal operation at the main intersection. Depending on the desired inbound and outbound sidewalks, some pedestrians are required to cross an extra street to make their desired movement compared to a conventional signalized intersection. The signals reduce the delay incurred by pedestrians at each crossing. Similar to conventional intersection. Design techniques for direct left turns are available. AIIR CAP-X (planning level) Synchro, SimTraffic VISSIM or similar microsimulation software 10. 1 Source for each illustration: Kittelson & Associates, Inc