Low Cost Evaluations

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Low Cost Evaluations
TRAFFIC SAFETY SYSTEMS MANAGEMENT SECTION -
Shawn A. Troy, PE North Carolina DOT - Traffic
Engineering Branch
Low Cost Pooled Fund TAC Meeting June 20, 2007
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Directional Crossover - 1

• Problem Statement
• High volume of traffic on mainline
• Vehicles attempt left turns from the side road
• Resulting in high number of crashes at the
  location
• Signal not considered due to signals on either
  side of intersection within 600
• Countermeasure
• Installation of a Directional Crossover
• Cost 55,000
• Project completion - June 30, 2000
• 5 Years and 7 Months - Before and After Data

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Directional Crossover - 1
4
Directional Crossover - 1
Looking East on Main
Looking East on Main
Picture 1
Picture 2
Looking East on Main
Looking West on Main
Picture 3
Picture 4
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Directional Crossover - 1
Before Collision Diagram
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Directional Crossover - 1
After Collision Diagram
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Directional Crossover - 1

• Results

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Directional Crossover - 1
Picture 1
Picture 2
Picture 3
Picture 4
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Directional Crossover - 1
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Directional Crossover - 2

• Problem Statement
• Congestion and high volume of traffic at the
  intersection
• Vehicles attempt left turns from the side road
• Resulting in high number of crashes at the
  location
• Countermeasure
• Installation of a Directional Crossover
• Cost 30,000
• Project completion - April 9, 1999
• 6 Years and 10 Months - Before and After Data

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Directional Crossover - 2
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Directional Crossover - 2
Looking South on US 158
Looking South on US 158
Picture 1
Picture 2
Looking South on US 158
Looking South on US 158
Picture 3
Picture 4
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Directional Crossover - 2
Looking North on US 158
Looking North on US 158
Picture 1
Picture 2
Looking North on US 158
Looking North on US 158
Picture 4
Picture 3
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Directional Crossover - 2
Before Collision Diagram
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Directional Crossover - 2
After Collision Diagram
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Directional Crossover - 2

• Results

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Directional Crossover - 2
Picture 1
Picture 2
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Directional Crossover - 2
Picture 1
Picture 2
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Directional Crossover - 2
Before Collision Diagram
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Directional Crossover - 2
After Collision Diagram
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Directional Crossover - 2

• Results

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Directional Crossover - 2
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Centerline Rumble Strips

• Problem Statement
• 11.5 mile segment of rural 2-lane roadway
• Section bordered on North and South by 4-lane
  divided roadway segments
• North is a 65 mph full control access segment
• South is a 55 mph partial control access segment
• Construction began in December 4, 2004 to convert
  2-lane segment to 4-lane divided roadway to match
  North and South segments
• During first 6 months of construction - 4 Fatal
  Head-On Crashes occurred

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Centerline Rumble Strips
Picture 1
Picture 2
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Centerline Rumble Strips

• Fatal Crash History
• January 1999 through June 2005

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Centerline Rumble Strips

• Countermeasure
• Installation of Centerline Rumble Strips for the
  remainder of the construction project
• Centerline rumble strips were installed in 5 days
  between July 19-28, 2005
• Total cost for the installation of milled rumble
  strips, traffic control and motorcyclist signing
  was 34,388

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Centerline Rumble Strips
Picture 1
Picture 2
Picture 3
Picture 4
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Centerline Rumble Strips
Picture 2
Picture 1
Picture 3
Picture 4
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Centerline Rumble Strips
Picture 2
Picture 1
Picture 3
Picture 4
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Centerline Rumble Strips

• Results

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Safety Evaluations

• Safety Evaluation Group
• 2004 15 projects 15
• 2005 95 projects (10 to be complete) 105
• 2006 102 projects (5 to be complete) 107
• 2007 41 projects (145 to be complete) 186
• Above are projects completed through 2002 - 102
  projects will be assigned from the 2003
  completions
• 190 Spot Safety project evaluations are on the
  web that were completed through December 31,
  2006
• http//www.ncdot.org/doh/preconstruct/traffic/Safe
  ty/ses/projects/completed.html

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AASHTO TIG-CMB

• Key Topic Areas
• Contact Information
• Background and Problem Identification
• Roadway Design Issues
• Maintenance Issues
• Benefits and Evaluation
• System Threats
• Barrier Design

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Contact Information
Shawn A. Troy, PE [phone] stroy_at_dot.stat
e.nc.us
Traffic Safety Unit Website http//www.ncdot.or
g/doh/preconstruct/traffic/TSU/default.html