Low Cost Safety Improvements Pooled Fund Study

Combination Centerline and Edgeline Rumble Strips

Overview

• Background
• Missouri’s Program
• Status of Data Collection
• Remaining Data Needs
• Evaluation Considerations

Background

Singe-vehicle ROR Crashes 39 percent of all fatal crashes (FARS, 1999) Included in Several NCHRP 500 Series Guidebooks Run Off Road, Head-on, Heavy Trucks, and Horizontal Curves. Run-Off Road Guidebook 3 Experimental Strategies Edge line “profile marking” Edge line rumble strips Modified shoulder rumble strips (narrow or no paved shoulder) Ranked 1st in Phase I Low cost and short implementation timeframe (< 1 year)

• Head-on Guidebook
  • Install centerline rumble strips
    • Tried strategy
  • Ranked 3^rd in Phase II
    • Low cost
    • Short implementation timeframe (< 1 year)
• Heavy Trucks and Horizontal Curve Guides
  • Shoulder and centerline rumble strips
    • Low to moderate costs
    • Short to medium implementation timeframe (1-2 years)
  • Heavy-vehicle drivers and horizontal curves
• Dual Application
  • Combination of centerline and edge line rumble strips
  • Not included in NCHRP 500 Series
  • Identified by Technical Advisory Committee
• NCHRP 17-32 Survey Results
  • Approximately 200 miles
  • 9 States
    • AZ, ID, KY, MO, OR, TX, UT, WA, WY

Missouri DOT Program

• Missouri DOT: Better Roads Brighter Future
  • Improve 85 percent of major route system in 5 years
• Part of Program – Install Dual Rumble Strips
  • Two predominant roadway types
    • 4-lane divided expressways
    • 2-lane roadways.
  • Includes both rumble strips and stripes
    • Mostly stripes
    • Stripes are placed on the edge line
  • Posted speed limits 55-65 mph
• Proposed Strategy Sites for FY 2007-2011
  • 1170 miles (170 sites for 2007)
  • 543 miles (75 sites for 2008)
  • 2351 miles (329 sites for 2009-2011)
• Additional Improvements
  • Surface improvements (overlay)
  • Shoulder improvements (upgrade to 4’ where possible)
  • Others (sign upgrades where necessary)

Status of Data Collection

Missouri Planned installations Those for SFY 2007 have begun MO DOT provided roadway/traffic data 2002 – 2005 MO DOT provided crash database 1997 – 2005

Remaining Data Needs

• MO Reference Sites
  • Sites planned for treatment in later years
• Additional States
  • Proactive evaluation
  • States planning to install combination rumble strips

Evaluation of Dual Application

• Crash Based Evaluation in MO
  • Proactive before/after evaluation
  • Evaluate sample of installations
  • Disaggregate analysis
    • Roadway type
    • Night and weather conditions

Evaluation Considerations

• Disaggregate analysis
  • Functional class
  • Night and weather conditions
• Including other states in evaluation
  • 4 States are Technical Advisory Committee Members

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