Effect of driving distractions on driver mental workload in work zone’s warning area

Traffic accidents are common in advanced warning areas of a maintenance work zone. One of the reasons for the accident is that the complex driving environment of the warning area makes drivers need to change lanes and speed frequently. Another reason is that driving distractions shift the driver's mental workload and make the drivers unable to complete the driving task well. The paper aimed to examine the impact of visual and cognitive distractions on the driver’s mental workload, eye movements, and driving behaviour when driving in advanced warning areas of the maintenance work zones. Thirty-two participants (mean age = 23.97 years) participated in the experiment and completed 3 advanced warning area simulation scenes. The road initial speed limit of simulation scenes was different: 60 km/h, 80 km/h and 100 km/h. The drivers needed to pass three scenes under three types of distraction tasks (no task, visual task and cognitive task). Six indices were used to evaluate the effect of the advanced warning area and the distracting secondary tasks on the driver's mental workload: two related to eye movements, two related to driver behavior, and two related to the electroencephalogram. The TOPSIS analysis was used to solve the problem of multi-evaluation indices comparison, sorting and selection. The results show that the driver has higher vehicle control ability under the distraction-free task condition than in other scenes. Furthermore, the impact of visual distraction on drivers is more significant than that of cognitive distraction, suggesting more visual attention is required for drivers when passing the complex working zone.