Study of Improved Signal-Based Merge Strategy in Work Zone Areas Based on Cellular Automata Simulation

Work zones have critical effects on traffic safety and efficiency. Previous researchers have developed lots of merge strategies to regulate drivers’ behaviours, which can be divided into early merge and late merge. As a special kind of late merge, signal-based merge strategy was proposed in recent years to reduce traffic conflicts and increase throughput at bottlenecks. Although traffic signal has been confirmed to improve the traffic in work zone areas effectively, the existing strategy still has limitations that require further improvements. In this research, an improved signal-based merge (IM) strategy was proposed to fulfil the research gaps. The strategy included a calculation method of green time considering the relationship between arrival traffic and the bottleneck’s capacity and a dynamic signal-phase conversion method. Based on the Cellular Automata simulation, the effectiveness of the IM strategy was verified through parameter sensitive analysis and comparative study with the existing merge strategies. The results showed that the IM strategy could lead to greater throughputs, lower traffic delays, less aggressive merge and more balanced queue length. Furthermore, the IM strategy also showed great stability in response to the changes of parameters and the imbalance of arrival traffic. Overall, the proposed IM strategy is considered more effective in improving the traffic management in work zone areas and is feasible to be applied in practice.