Analysis of Crash Severity of Texas Two Lane Rural Roads Using Solar Altitude Angle Based Lighting Condition

Many studies have examined the impact of factors affecting accident severity in rural areas; however, little attention has been paid to different lighting conditions (LCs), and less detailed categories precise determining twilight. In this paper, solar altitude angle (SAA), as a basis for differentiating categorizing LCs, is proposed investigate explanatory variables much greater detail. For each LC, namely, dark, twilight, dark lit (dark with street lights) daylight, separate random parameter models are developed impacts some on crash injury data 2017 2018 two lane roads Texas. The model estimation results indicated that LCs various contributing factors, indeed, severity, further stressing significance investigating crashes based SAA. key differences include location, marked lane, grade direction, no passing zone, shoulder width, weekday collision type. important findings were developing artificial at intersections LED raised pavement markers could lead enhanced road safety under LCs. Furthermore, increasing width straight segments decreasing severe daylight conditions.