Design speed is defined as "a speed selected as a basis to establish appropriate geometric design for a particular section of road" in the 1999 TAC Geometric Design Guide. While the TAC Design Guide has enhanced the various definitions of speed and placed an emphasis on the need for designers to recognize that operating speeds may be different from design speed assumptions, it does not provide specific guidance on how to choose an appropriate design speed. As part of TAC's commitment to update the Geometric Design Guide on a regular basis two working papers have recently been completed to reflect new international developments in the areas of design consistency and design speed. This paper presents an overview of the salient findings from the working paper on design speed choices. The working paper is based on an analysis of design speed practices around the world.
Samenvatting