Cell transmission model for mixed traffic flow of cars and trucks on highways

LIU Ying; ZHANG Peng

doi:10.11860/j.issn.1673-0291.20230150

Abstract：Addressing the issues of decreased traffic flow stability,increased traffic safety risks,and reduced operational efficiency caused by mixed passenger and freight traffic,this paper constructs a multi-lane mixed passenger and freight traffic flow cell transmission model to study the characteristics of highway mixed traffic under different truck penetration rates from a macroscopic perspective. Initially,utilizing microscopic car-following models,the fundamental diagram characteristics of homo-geneous passenger car and truck traffic flows are analyzed,and a fundamental diagram model of mixed traffic flow under different truck penetration rates is proposed. Subsequently,specific parameters are employed to characterize the effects of lane-changing and limited acceleration on the reduction of road traffic capacity,depicting the impact of trucks on straight and lane-changing traffic flow in mixed traf-fic. The Logit model is used to calculate lane-changing traffic volume under the influence of multiple factors,thus constructing a cell transmission model of multi-lane mixed passenger and freight traffic flow. Finally,the model's effectiveness is verified through multi-scenario highway simulation experi-ments. The research results show that the proposed model can accurately simulate the evolution of mixed traffic flow on highways;truck penetration rate is a critical factor affecting mixed traffic opera-tions,and when traffic incidents reduce the number of lanes,a truck penetration rate exceeding 0.6 leads to persistent traffic congestion. The study provides analytical tools for researching mixed pas-senger and freight traffic flow characteristics and offers theoretical methods for traffic management and guidance strategy formulation under mixed traffic conditions.