Interchange Deceleration Lane Design Based on Naturalistic Driving Speeds and Deceleration Rates

The objective of this study is to determine the minimum lengths of freeway deceleration lanes based on naturalistic driving speeds and deceleration rates from the Naturalistic Driving Study (SHRP 2 NDS) database. SHRP 2 NDS has the distinct advantage of providing insight into driver behavior based on a wide-ranging collection of data regarding the driver, the vehicle, and the environment, whereas previous studies of this subject relied primarily on crash data, radar data, computer simulations, and driving simulators. Ten study locations that are located on I-75 in Florida with varying deceleration lane lengths and off-ramp lengths were used. The analysis included (1) speed distribution on different lengths of freeway deceleration lanes and off-ramps based on polynomial regression models; (2) drivers’ behavior, including brake pedal usage, critical speed change point detection, and the distribution of deceleration rates compared with the American Association of State Highway and Transportation Officials (AASHTO) Green Book assumptions; and (3) a new method to determine the minimum deceleration lane lengths based on naturalistic driving speeds and deceleration rates. The results revealed that (1) typically, vehicle speeds reduced by 10% to 25% on deceleration lanes while 75% to 90% on off-ramps; (2) deceleration rates on deceleration lanes and off-ramps before critical speed change points are lower than assumptions from the Green Book; and (3) deceleration lanes can be shorter when off-ramps are long at diamond interchanges (e.g., greater than 1,550 ft).


  • English

Media Info

  • Media Type: Digital/other
  • Features: Figures; References; Tables;
  • Pagination: pp 57-78
  • Monograph Title: SHRP 2 Safety Data Student Paper Competition 2017–2019
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 01702874
  • Record Type: Publication
  • Files: TRIS, TRB, ATRI
  • Created Date: Apr 23 2019 9:16AM