Traffic Flow Characteristics and Lane Use Strategies for Connected and Automated Vehicles in Mixed Traffic Conditions

Zijia Zhong,Liuhui Zhao,Joyoung Lee,Meng Meng

doi:10.1155/2021/8816540

Abstract

Managed lanes, such as a dedicated lane for connected and automated vehicles (CAVs), can provide not only technological accommodation but also desired market incentives for road users to adopt CAVs in the near future. In this paper, we investigate traffic flow characteristics with two configurations of the managed lane across different market penetration rates and quantify the benefits from the perspectives of lane-level headway distribution, fuel consumption, communication density, and overall network performance. The results highlight the benefits of implementing managed lane strategies for CAVs: (1) A dedicated CAV lane significantly extends the stable region of the speed-flow diagram and yields a greater road capacity. As the result shows, the highest flow rate is 3400 vehicles per hour per lane at 90% market penetration rate with one CAV lane. (2) The concentration of CAVs in one lane results in a narrower headway distribution (with smaller standard deviation) even with partial market penetration. (3) A dedicated CAV lane is also able to eliminate duel-bell-shape distribution that is caused by the heterogeneous traffic flow. (4) A dedicated CAV lane creates a more consistent CAV density, which facilitates communication activity and decreases the probability of packet dropping.

Highlights

E goal of this study is to investigate the impact of different lane use strategies under mixed traffic conditions at vehicle trajectory, as well as lane, level
With a subsequent test on an 18 km segment of SR-99, the research team found that deploying vehicle awareness device- (VAD-) equipped vehicles along with managed lane strategies was helpful in improving corridor-level traffic flow under low and medium connected and automated vehicles (CAVs) market penetrations [14]
Aggregated data are collected at 5minute intervals, and the raw data are collected at each simulation time step. e analysis is performed on five aspects: (1) traffic flow characteristics, (2) headway distribution, (3) fuel consumption, (4) wireless communication, and (5) overall network performance

Summary

Introduction

E goal of this study is to investigate the impact of different lane use strategies under mixed traffic conditions at vehicle trajectory, as well as lane, level. An analytical model for determining the optimal managed lane strategy was proposed in [5], where the maximum system throughput in a mixed traffic condition could be calculated under the assumption of random vehicle distribution on a freeway facility.

Results

Conclusion