Estimating the crash reduction and vehicle dynamics effects of flashing LED stop signs : final report.

Details

• Creators:
  Davis, Gary A. ; Hourdos, John ; Xiong, Hui
• Corporate Creators:
  University of Minnesota. Dept. of Civil Engineering
• Corporate Contributors:
  Minnesota. Dept. of Transportation. Research Services & Library
• Subject/TRT Terms:
  • Stop signs
  • Flashing traffic signals
  • Driver performance
  • Crash modification factor
  • Crash causes
• Publication/ Report Number:
  2014-02
• Resource Type:
  Tech Report
• Geographical Coverage:
  United States
• Corporate Publisher:
  Minnesota. Dept. of Transportation. Research Services & Library
• Abstract:
  A flashing LED stop sign is essentially a normal octagonal stop sign with light emitted diodes (LED) on the ; stop sign’s corners. A hierarchical Bayes observational before/after study found an estimated reduction of ; about 41.5% in right-angle crashes, but with 95% confidence this reduction could be anywhere between 0% ; and 70.8%. In a field study, portable video equipment was used to record vehicle approaches at an ; intersection before and after installation of flashing LED stop signs. After installing the flashing stop signs, ; there was no change in the relative proportion of clear stops to clear non-stops when minor approach ; drivers did not face opposing traffic, but the relative proportion of clear stops increased for drivers who did ; encounter opposing traffic. Random samples of 60 minor approach vehicles were selected before and after ; installation of flashing LED stop signs and speeds for these vehicles when about 500 feet from the ; intersection, and average deceleration rates over the final 500 feet, were estimated using trajectory-based ; methods. Average approach speeds tended to be highest in June, somewhat lower in July, and lower yet in ; September and November, with September and November having roughly equal average speeds. The ; average deceleration rates showed a similar pattern.
  More +
• Format:
  PDF
• Funding:
  CTS Project # 2011003 ; (C) 89261 (WO) 195
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/32160/dot_32160_DS1.pdf
• File Type:
  [PDF - 4.22 MB]
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha-512:bf282ee9552053b971bc38d02b061ab934014565d670d157e22c87941aaaa74e82604f7f01497342aee19e159d5d39d1865b0055e081789f6c1efffc96f7cc20