Road curve superelvation design: current practices and proposed approach

摘要

Horizontal alignment design standards in the United States and Australia have two basic common features: Firstly, the absence of a single nation wide maximum, Superelevation rate and, secondly, designers' Freedom in applying above-minimum values for Curve radii. Taking into account the proven Dependence of operating speed on curve radius, Australian standards introduce the concept of radius, Environment(characterising highway sections as a Whole)to be used alongside the traditional design Speed concept(corresponding to individual design And incorporate consistency checks as a feedback Loop in the design process.