Drivers’ Heart Rate Variability Analysis under Different Tunnel Cross-section Designs: A Case Study

As a special component of the highway traffic facilities, the tunnel could might affect drivers’ physiology because of the limited space. Although the highway tunnel design guidelines are met, the different cross-section designs would have different effects on drivers. The aim of this study was to analyze the drivers’ physiology difference when driving in two tunnels with different cross-section designs. The two different tunnel cross-section designs had the same tunnel construction clearance. One of the design has an arc-shaped top, and the other is almost rectangular. Hence, a driving simulator study was conducted and drivers’ heart rate variability (HRV) data were collected and analyzed. It was found that (1) for the passenger car drivers, who have a lower viewpoint, their HRV data had no significant difference; (2) for the commercial vehicle drivers, who have a higher viewpoint, the AVNN indicator showed significant differences.