Impact of Road Sign on Traffic Congestion during Road Repair: A Cellular Automaton Model Study

¹ School of Engineering, The University of Tokyo, Tokyo, Japan
² Graduate School of Informatics and Engineering, The University of Electro-Communications, Tokyo, Japan

^* Corresponding author: This email address is being protected from spambots. You need JavaScript enabled to view it.

Published online: 12 September 2025

Abstract

This study investigates the impact of road signs on traffic congestion during road repairs using a cellular automaton (CA) model. The model simulates an urban dual-lane one-way road, incorporating a designated work zone. Three scenarios are analyzed: Without Sign, With Sign, and Combined Signs. The With Sign scenario includes advance warning signs placed before the work zone, encouraging gradual deceleration and safe lane changes, while the Combined Signs scenario integrates additional signage in the adjacent lane to optimize vehicle spacing and minimize congestion. Simulation results demonstrate that the combined signage approach achieves the most significant traffic improvements by reducing risky lane changes and promoting smoother speed adjustments, thereby alleviating congestion. Additionally, heatmap and density-flow analyses demonstrate improved lane utilization and reduced bottlenecks in scenarios incorporating road signs. The findings underscore the importance of integrating multiple coordinated road signs with behavioral insights for enhanced traffic management near work zones.