The influence of road design speed, posted speed limits and lane widths on speed selection: a literature synthesis

Drivers select the speed at which they travel as a function of a variety of driving clues and risk assessment, directly affecting the operating speed of that road. Resulting speed distributions are routinely used to justify posted speeds. Operating speeds are fundamental to the development of any roadway corridor and are used to determine appropriate roadway design elements. Roadway corridors are generally developed to maintain the tenens of cross section consistency, operating speed consistency, and driver work-load consistency. These tenets are interrelated within a road corridor and must be designed to ensure appropriate speed choices are made. Some empirical evidence suggests that narrower roads, and narrower lanes on roads, lead to slower travel speeds. In contrast, the literature reveals that the effects of narrower cross-sections to lower traffic speeds, and associated crash frequencies, have been inconsistent. Some researchers have concluded that reducing lane widths had no impact on speed selection. Moreover, a lack of geometric design consistency and the associated disparity with drivers’ expectations has led to increased crash rates when differences between design and posted speeds exist. Whilst it is important to be aware of corridor characteristics such as the road grade, cross-section and surface conditions, there has been insufficient research to accurately understand their impacts on speed choice (distributions) and associated design and posted speeds. This paper addresses the gap in the literature and provides a current and comprehensive literature synthesis on this important subject, identifying research gaps and critical research needs moving forward.

• Record URL:
  http://www.atrf.info/papers/2013/index.aspx
• Authors:
  • Deller, J
• Conference:
  • Australasian Transport Research Forum (ATRF), 36th, 2013, Brisbane, Queensland, Australia
• Publication Date: 2013-10

Language

• English

Media Info

• Pagination: 14p
• Monograph Title: Transport and the new world city: 36th Australasian Transport Research Forum (ATRF), October 2nd-4th 2013, Brisbane

Subject/Index Terms

• TRT Terms: Design speed; Drivers; Highway design; Highways; Literature reviews; Operating speed; Speed limits; Traffic lanes; Width; Width
• Uncontrolled Terms: Road design and asset management
• ATRI Terms: Design speed; Literature review; Operating speed; Road design; Speed limit; Traffic lane; Width
• Subject Areas: Highways; Law; I82: Accidents and Transport Infrastructure; I83: Accidents and the Human Factor;

Filing Info

• Accession Number: 01503326
• Record Type: Publication
• Source Agency: ARRB
• Files: ITRD, ATRI
• Created Date: Jan 6 2014 10:59AM