Low Cost Safety Improvements Pooled Fund Study

Combination Centerline and Edgeline Rumble Strips

Dr. Frank Gross, VHB

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)

Background

Head-on Guidebook Install centerline rumble strips

• Tried strategy Ranked 3rd 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

Background

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

Missouri DOT Program

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