Safety assessment of cooperative adaptive cruise control truck platooning on freeways work zones

Work zones on freeways, especially those marked by complex merging dynamics, present multifaceted challenges for traffic safety and operations. The integration of Connected and Autonomous Vehicles (CAVs), equipped to execute intricate maneuvers such as platooning, introduces an additional layer of complexity. While existing research on heavy vehicle platooning in work zones has been limited, there is a recognized need to investigate the safety impacts of heavy vehicles equipped with CAV technology in these work zones. This study addresses this research gap by employing VISSIM microsimulation to investigate the safety implications of Cooperative Adaptive Cruise Control (CACC) truck platooning in these contexts. The study examines various scenarios by deploying lane change warning signs at differing distances upstream of work zones. The findings reveal that early merge strategies, with signs positioned at least one mile ahead, result in a remarkable 300% reduction in traffic conflicts, ensuring smoother platoon dissolution and improved lane change execution in comparison to late merge strategies. Additionally, the inclusion of longer truck platoons in early merge scenarios leads to a 40% reduction in traffic conflicts, signifying heightened safety, particularly in high traffic volume conditions. Conversely, late merge situations, particularly when coupled with extended platoons and high traffic volumes, experience substantial declines in safety and operational efficiency. The study emphasizes that, although platooning offers significant advantages under controlled traffic conditions, Infrastructure Owners and Operators (IOOs) should collaborate with stakeholders, including trucking companies and law enforcement agencies, to adapt their infrastructure to accommodate truck platooning. These adaptations may encompass the formulation of merging and platoon-splitting procedures, the design and maintenance of signage and signal systems, the establishment of appropriate speed limits within work zones, and the development of protocols for emergency response.