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From page 46... ... 46 To study and find the conditions amenable to dedicating lanes for CAV users, the team conducted a modeling and simulation-based study of CAV driver behavior on DLs on a selected set of diverse case-study sites. This chapter details the process that was used to select the case study sites based on the project objectives. Read the entire page →
From page 47... ... Case Study Site Selection 47 This suburban test site includes six interchanges and two dedicated on-and-off ramps for an HOV lane that is separated from the GPLs. The average distance between interchanges is approximately 1.2 miles, yielding 0.6 miles and 2 miles of minimum and maximum interchange spacing, respectively. Read the entire page →
From page 48... ... 48 Dedicating Lanes for Priority or Exclusive Use by Connected and Automated Vehicles 1,500 vphpl of peak HOV traffic volumes. This simulation model is currently available in the U.S.DOT's Open Source Application Development Portal for academic/research use. Read the entire page →
From page 49... ... Case Study Site Selection 49 separate the lanes and to indicate no lane changing and no access. Access points between the dedicated HOV-2 lanes and the mixed-use lanes are permitted only along areas with dashed lane striping. Read the entire page →
From page 50... ... 50 Dedicating Lanes for Priority or Exclusive Use by Connected and Automated Vehicles 4.1.3 I-15 Corridor, San Diego, California The I-15 case study site is made up of a 22-mile stretch of the I-15 corridor facility and associated parallel arterials. It extends north-to-south from the interchange with SR-78, just below the City of Escondido, California, to the interchange with Balboa Avenue, approaching San Diego, California. Read the entire page →
From page 51... ... Case Study Site Selection 51 off-peak hours in the peak direction. The measured daily VMT varies from the average value of all days observed by no more than a 10% margin. Read the entire page →
From page 52... ... 52 Dedicating Lanes for Priority or Exclusive Use by Connected and Automated Vehicles of passenger vehicles with a small proportion made up of commercial trucks. On this corridor, transit is not significant enough to affect operations greatly; therefore, transit was not explicitly modeled. Read the entire page →
From page 53... ... Case Study Site Selection 53 Driver behavior was calibrated in CORSIM per Minnesota DOT guidelines. Vissim models were calibrated as well to replicate existing travel speeds and congestion levels during the a.m. Read the entire page →
From page 54... ... 54 Dedicating Lanes for Priority or Exclusive Use by Connected and Automated Vehicles The existing calibrated models were in CORSIM format and owned by the Minnesota DOT, which presented significant challenges to modeling CAV behavior due to limitations in utilizing external API to code varying driver behaviors. Traffic count and speed data along the ramps and mainline were obtained through Minnesota DOT's Regional Traffic Management Center detector data (Minnesota DOT 2017) Read the entire page →
From page 55... ... Case Study Site Selection 55 I-290 and within the I-290 median for the eastern half of the study corridor; however, due to limited interaction with the freeway, transit -- including commuter rail -- was not included in the microsimulation modeling. VMS are present indicating travel time along the corridor. Read the entire page →
From page 56... ... 56 Dedicating Lanes for Priority or Exclusive Use by Connected and Automated Vehicles Transportation (Michigan DOT) traffic count web portal for ramps and mainline counts along the corridor (Michigan DOT 2018) Read the entire page →
From page 57... ... Case Study Site Selection 57 This corridor experiences very little diversity in demand conditions and traffic patterns, and currently operates at a high level of congestion throughout most typical days. The only parallel alternate route is SR-355, an arterial corridor with signalized intersections and significant business activity. Read the entire page →
From page 58... ... 58 Dedicating Lanes for Priority or Exclusive Use by Connected and Automated Vehicles (see Figure 4.11) Read the entire page →
From page 59... ... Case Study Site Selection 59 consistently declines below 45 mph over a 90-day period, a policy that is largely the result of the project's initial funding through the Federal Urban Partnership Agreement. The Florida DOT estimates that about 2% to 3% of the traffic in the express lanes is travelling toll free. Read the entire page →
From page 60... ... 60 Dedicating Lanes for Priority or Exclusive Use by Connected and Automated Vehicles Source: NCHRP 20-102(08) project team; base map data from Florida DOT (2018) Read the entire page →
From page 61... ... Case Study Site Selection 61 Figure 4.14. Case study characterization based on model availability. Read the entire page →
From page 62... ... 62 Dedicating Lanes for Priority or Exclusive Use by Connected and Automated Vehicles Figure 4.16. Case study characterization based on routing features. Read the entire page →
From page 63... ... Case Study Site Selection 63 4.2.1.8 Existence of ITS Strategies ITS strategies are implemented to maximize roadway carrying capacity and increase safety. Concurrent implementation of ITS strategies with CACC DLs may have either synergistic or conflicting effects on roadway capacity and driver safety. Read the entire page →
From page 64... ... 64 Dedicating Lanes for Priority or Exclusive Use by Connected and Automated Vehicles throughout the day at the imposed area. Other operating rules may include the enforcement of left-lane passing only laws, which may involve safety concerns for vehicles that must pass multiple platooned vehicles to find an acceptable gap for a lane change. Read the entire page →
From page 65... ... Case Study Site Selection 65 access to the facility. Driver lane-changing behaviors on both GPLs and DLs will be affected by advanced knowledge of access availability. Read the entire page →
From page 66... ... 66 Dedicating Lanes for Priority or Exclusive Use by Connected and Automated Vehicles the traffic flow performance under a mixed-use case including CAV and non-CAV was critical to determining their traffic impacts, so this criterion was given a high priority. 4.3 Selected Case Study Sites The project team used the scoring criteria discussed in the preceding sections of this chapter to score and rank the nine candidate case study sites. Read the entire page →
From page 67... ... Northern Virginia San Mateo, California San Diego, California St. Paul, Minnesota Minneapolis, Minnesota Chicago, Illinois Detroit, Michigan Maryland Miami, Florida Ca se S tu dy S ite C ha ra ct er is tic s Characteristics Urban ● ● ● ● ● ● Suburban ● ● ● ● ● Rural ● Availability of Model and Data Open-source ● ● Available on Request ● ● ● ● ● ● ● Unavailable Demand Levels Low ● ● ● ● ● Medium ● ● ● ● ● ● ● High ● ● ● ● ● ● ● ● ● Size of Model Length (Miles) Read the entire page →
From page 68... ... Northern Virginia San Mateo, California San Diego, California St. Paul, Minnesota Minneapolis, Minnesota Chicago, Illinois Detroit, Michigan Maryland Miami, Florida M an ag ed L an e Ch ar ac te ri sti cs Characteristics Number of Lanes 1 2 2 1 1 1 1 1 2 User Types HOV ● ● ● ● ● ● ● ● ● HOT ● ● ● ● ● Transit ● ● ● ● ● ● ● ● ● Trucks ● Operating Rules Time of Day Operation ● ● ● ● ● ● ● ● Time of Day Pricing Congestion Pricing ● ● ● Physical Barriers None ● Lane-marking ● ● ● ● ● ● Delineators ● ● Separated Access Point Throughout ● ● Limited ● ● ● ● ● ● ● Fe as ib ili ty Modeling Platform API Unavailable ● API Available ● ● ● ● ● ● ● ● Driver Behavior Not Calibrated Calibrated ● ● ● ● ● ● ● ● ● Table 4.3. Read the entire page →
From page 69... ... Case Study Site Selection 69 Parameter Scoring and Criteria 1. Case Study Characteristics Geographic Characteristics 3 = Urban region. Read the entire page →
From page 70... ... 70 Dedicating Lanes for Priority or Exclusive Use by Connected and Automated Vehicles With regard to parameters for which variety was preferred, the case study sites that represented a diverse set of values were given higher scores. For example, St. Read the entire page →

From page 46...

... 46 To study and find the conditions amenable to dedicating lanes for CAV users, the team conducted a modeling and simulation-based study of CAV driver behavior on DLs on a selected set of diverse case-study sites. This chapter details the process that was used to select the case study sites based on the project objectives.