## 2 Literature Review  
The unique visual environment of urban underground roadways can impact drivers' visual and psychological states, thereby influencing their driving behavior. Therefore, examining the effects of underground road environments on driver behavior from the perspectives of driver vision, psychology, and more plays a crucial role in enhancing underground road safety. Among them, the tunnel environment has a significant impact on visual perception. [PERSON] et al. proposed four traffic visual guidance schemes for the diversion and convergence zones of urban underground roads, and studied their impact on driving behavior through simulated driving experiments [10]. [PERSON] et al. investigated the influence of the sidewall effect on drivers in urban tunnels and found significant differences in the distribution of driver attention and vehicle stability among different lanes, with the left side being the most significant [11]. Moreover, the geometric design of underground roads can affect driving stability. Therefore, [PERSON] proposed an optimal value for the alignment design index of an underground road access ramp based on the driver's physiological index through a driving simulation test [12]. Additionally, changes in the geometric shapes of underground roadways can affect drivers' psychological states, visual load, driving speeds, and acceleration. [PERSON] et al. found that the saccadic angle dispersion of drivers in ultralong urban underwater tunnels increased with the radius [13]. [PERSON] et al. also discovered that the longer the urban tunnel, the more dispersed the distribution of driver gaze points [14]. In addition, researchers have found that the geometric indicators of urban underground roads affect vehicle speed and driver heart rate. For instance, [PERSON] et al. conducted on-road experiments and found that the longitudinal slope had a significant impact on the growth rate of driver heart rate, with a higher increase observed for downhill sections than for uphill sections [15]. [PERSON] et al. found that the lane width and shoulder width of three-lane underground urban highways significantly affected the driving speed, with lane width having a greater impact than shoulder width [16]. Furthermore, tunnel lighting and illumination also have a certain impact on tunnel driving safety. [PERSON] et al. [17] found that at lower speeds, the at least four times stopping sight distance (4 SSD) of advanced vehicle lighting systems (AVLL) is crucial for improving driver speed consistency and control feel within curves, helping to reduce sudden speed adjustments. [PERSON] et al. [18] found through experimental analysis that in road tunnels where vehicle speed limits are less than 60 km per hour, under vehicle headlight illumination, human visibility of obstacles exceeds stopping distance. However, analyzing the visual characteristics and psychological load of the driver does not directly reflect the risk level of driving behavior. It primarily reflects the driver's cognitive and psychological states. Therefore, one must analyze the driving characteristics and risks of vehicles based on lateral and longitudinal acceleration data. Acceleration is an important indicator of vehicle driving characteristics. It is also a core indicator for analyzing the stability, safety, comfort, and driving behavior of a vehicle. The driving characteristics of a car are primarily influenced by the longitudinal, lateral, and vertical accelerations. Lateral acceleration is generated by the centrifugal force when the vehicle is turning and is the main indicator for describing the cornering state, driving stability, and comfort of the car. Many previous studies have established statistical models to study lateral acceleration. For example, [PERSON] et al. used lateral acceleration as an indicator to evaluate the safety level of curves and analyzed the correlation between driving behavior factors and road curvature using a linear regression model [19]. [PERSON] et al.