Evaluation of Centreline ATLM along Curves in Mountainous Roads

Abstract

Centreline Audio Tactile Line Marking (ATLM) was installed on a popular narrow road in the Adelaide foothills. A before-after evaluation was conducted to assess the ATLM potential for influencing lane position/crossing and speed along four trial curves. Vehicle lane position and speed at those curves, and between-site travel times were analysed. . Post treatement, all vehicle types tended to safely shift towards the edgeline along right-hand curves. However, variability along left-hand curves existed amongst the four sites. Generally, the treatment did not appear to reduce lane crossing frequency on curves, except at one site. Centreline ATLM did not appear to induce a speed decrease along curves. Nonetheless, a slight reduction of the average travel speed along the treated route may indicate a generalised speed calming effect.

The study suggests merit for centreline ATLM along curves regarding lane positioning, but a limited effect on voluntary lane crossing and speed.