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Report
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Publication Number: FHWA-RD-97-106

Rural Public Transportation Technologies: User Needs and Applications FR1-798

APPENDIX D

ACCIDENT FREQUENCY DISTRIBUTIONS FOR SELECTED INTERCHANGE ELEMENTS

This appendix presents a series of accident distribution plots for camp segmens, ramps, speed-change lanes, and combinations thereof. These include:

  • Ramp proper segments, off-ramps only (rear-end accidents exluded from frequency distributions) in figure 9.
  • Speed-change lanes (total and fatal and injury multiple-vehicle accidents) in figure 11.
  • Entire ramps, off-ramps only (rear-end accidnets excluded from frequency distributions) figure 10.
  • Entire ramps plus adjacent speed-change lane (total and fatal and injury multiple-vehicle accidents) in figure 12.
  • Urban diamond off-ramps (total and fatal and injury multiple-vehicle accidents) in figure 13.
  • Urban parclo and free-flow loops off-ramps (total and fatal and injury multiple-vehicle accidents) in figure 14.
  • Urban outer connection off-ramps (total and fatal and injury multiple-vehicle accidents) in figure 15.

In addition, 1-year accident (total and fatal and injury multiple-vehicle accidents) for the 551 entire ramps and the 737 ramp proper segments studied in this report are presented in figures 16 and 17, respectively, comparing the 3 years of accident data for 1993 through 1995.

Figure 9. Accident Frequency Distribution for Ramp Proper Segments, Off-Ramps Only (Rear-End Accident Excluded)

Figure 10. Accident Frequency Distribution for Entire Ramps, Off-Ramps Only-Ramps Only (Rear-End Accidents Excluded)

Figure 11. Accident Frequency Distibutions for Speed-Change Lanes

Figure 12. Accident Frequency Distributions for Entire Ramps, Including the Adjacent Speed-Change Lane

Figure 13. Accident Frequency Distributions for Urban Diamond Off-Ramps

Figure 14. Accident Frequency Distributions for Urban Parclo and Free-Flow Loop Off-Ramps

Figure 15. Accident Frequency Distributions for Urban Outer Connection Off-Ramps

Figure 16. Annual Accident Frequency Distributions for Entire Ramps (1993-1995)

Figure 17. Annual Accident Frequency Distributions for Ramp Proper Segments (1993-1995)

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