## 1 Introduction
studied the impact of traffic volume, traffic composition, and transition area length on the traffic characteristics of work zones through micro-simulation and proposed a method for predicting the traffic safety risk. Their results indicated that vehicle speed and transition area length had a significant impact on traffic safety in work zones [17; 18]. [PERSON] et al. used driving simulation and unsupervised machine learning clustering to analyze driving behavior in transition areas with different lane closure forms. The numbers of aggressive and conservative drivers in the work area were significantly higher than that of ordinary drivers, and drivers in the left lane were more aggressive than those in the right lane, resulting in vehicle speeds being too high or too low and increasing the dispersion of speed [19]. [PERSON] et al. conducted a questionnaire survey on drivers in work zones based on their stated preferences and found that road conditions, traffic conditions, transition area length, and speed limit were important factors affecting drivers' choice of merging location and traffic safety in work zones [20]. [PERSON] et al. constructed a multi-stage analytical model for lane-changing behavior in work zones based on a driving simulation, where the lateral and longitudinal acceleration of vehicles undergoing merging increases and the merging distance decreases when the traffic volume is high [21]. Based on video data, [PERSON] et al. proposed an estimation method for the rear-end collision of vehicles in a transition area using the logit model. If vehicles fail to complete merging before reaching the end of the transition area, the collision risk will be increased to about 3.3 times that of vehicles that complete merging in advance, and sufficiently increasing the transition area length will improve safety in work zones [22]. In terms of transition area length, [PERSON] et al. used a driving simulation to analyze lateral position, collisions, and other driving behaviors of drivers in a transition area of 30-160 m. Their results indicated that smaller transition area lengths would reduce the sight distance and reaction time of drivers and increase the traffic safety risk in work zones [23]. [PERSON] et al. analyzed the impact of a 100-500 m transition area length on traffic efficiency and safety and concluded that the number of lanes is a key factor affecting the transition area length. The transition area length for a three- or four-lane work zone should be 300 m, and the transition area length for a two-lane work zone should be 200 m [24]. [PERSON] et al. used micro-simulation, driving simulation, and real vehicle experiments to analyze the difference between a joint merge transition area and a traditional transition area. When the joint merge transition area was 200-250 m, the vehicle running speed was consistent with the traditional transition area, and driving workload was lower, resulting in better traffic safety [25; 26; 27]. Based on the theory of vehicle collision avoidance, [PERSON] calculated the longitudinal distance for lane changing and emergency stopping in work zones and found that the transition area length should be 75-193 m [28]. At present, most relevant studies on transition areas use theoretical calculations, traffic simulation, and driving simulation, and their results differ and are difficult to verify [29; 30]. The impacts of different transitional area conditions on drivers' psychophysiological indicators are unclear, and there is a lack of research comparing driving behavior characteristics under different lane closure forms.