Effectiveness of Pavement Grooving in Skidding Prevention on Horizontal Curves

Pavement grooving is an accepted remedial measure to improve skid resistance and reduce crash rates on horizontal curves. However, besides experience-based guidelines, currently no mechanistic procedure is available for quantitative evaluation of the effectiveness of a pavement grooving design in skidding prevention on horizontal curves. To ensure driving safety on wet horizontal curves in particular, there is a practical need for a reliable procedure to determine the effectiveness of a pavement grooving design in increasing tire–pavement skid resistance and the maximum safe driving speed. With the aim to bridge the knowledge gap, this paper presents a computer simulation procedure based on the finite-element method to evaluate the effectiveness of a pavement grooving design in terms of its ability to increase the maximum safe vehicle speed and reduce skidding potential on a wet horizontal curve. For illustration, three common grooving designs were considered, each having a different groove width, depth, and spacing. For each grooving design, two orientations of grooving, namely longitudinal and transverse grooves, were studied. The simulation model allowed different operating conditions to be analyzed, including different geometric dimensions of a horizontal curve, pavement surface properties, and pavement surface water film thicknesses. The analysis not only confirmed past observations and measurements that longitudinal grooving was significantly more effective than transverse grooving in raising pavement skid resistance and the maximum safe driving speed on horizontal curves, but also quantitatively provided their respective magnitudes of improvement.