The Effect of Audio Warning on Driver’s Cognitive Load and Lane-Changing Behavior in Work Zone Area

Mandatory lane changing in highway work zones impose great threatens. This study aims to propose and verify an in-vehicle audio warning for improving drivers’ lane-changing behavior under different traffic status through a driving simulator experiment. Three traffic density levels and five audio warning positions were set as impact factors, forty-three licensed drivers were recruited to complete the test. The results show that: (1) Traffic density is a key factor affecting driver’s cognitive load and driving behavior. Although drivers at high traffic density condition maintained low speed and deceleration, the cognitive load and the speed of wheel steering when changing lanes increased significantly, which might lead to traffic safety issues; (2) The efficacy of audio warning is closely related to traffic density conditions. At low traffic density condition, the additional information provided by audio warning would increase drivers cognitive load, and made the driver take large deceleration. While at high traffic density condition, drivers cognitive load decreased with the aid of audio warning, and they would adopt lower deceleration and wheel steering when the warning was released 1000m upstream of the work zone area.