This study was charged with the task of determining the effectiveness of edge line pavement markings on rural two-lane highways in Texas and considered two major evaluation approaches: crash statistics analysis and detailed investigation of driver responses. Crash statistics comparisons were made for Texas rural two-lane highways with and without edge lines. In addition to general crash frequency analysis, varying traffic lane and shoulder widths, roadway curvature, and factors such as crash type, intersection presence, light condition, surface condition, crash-supporting factors, severity, driver age, and driver gender were considered for 9,774 crashes that occurred between 1998 and 2001. The research found that edge-line treatments on rural two-lane roadways may reduce crash frequency with the highest safety impacts occurred on curved roadway segments. The next stage was focused on complex investigations of edge lines impacts on driver behaviorand reactions, including vehicle navigational and positioning issues, speed selection, and effect on driver visual perception. Stationary traffic observation, test driving, and several laboratory experiments were conducted on the selected rural two-lane highways with different roadway width before and after edge lines placement. Studies indicated that edge line treatments affect vehicle transverse position, reduce vehicle fluctuation around trajectory centerline, reduce driver stress level during nighttime driving, improve driver’s estimation of roadway curvature, and increase the distance for intersection advance recognition.
Abstract