Mathematical evaluation of the safety effects of embankment on curves for roads in the Southern African context

Abstract

Curves have always been a safety concern in roadway design. More crashes tend to occur on curved sections than on tangent sections. Factors influencing safety concerns on curves, such as design speed and, embankment angles, were investigated through mathematical models based on the design guidelines currently used in South Africa and the Green Book. The effect of gradient did not affect the maximum travel speed that can be obtained on a specific radius with an applied superelevation rate. Minimum radii were found to pose the highest risk, and it is recommended to impose desirable minimum limits rather than relying on theoretical minimum values to mitigate these risks.