a focus technology of the american association of state highway and transportation officials...
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A Focus Technology of theAmerican Association of State Highway and Transportation Officials (AASHTO)
Technology Implementation Group (TIG)
CABLE MEDIAN BARRIERBest Practices Guidelines
Cable Median Barrier
Share & Sponsor Technology Transfer
Promote Transportation Advancements
Encourage Implementation
Cable Median Barrier
Why Median Barriers ….
200 Miles of Highway = 1 Crossover Fatality
250 Killed Annually in Crossover Crashes
23,139 Road Departure Fatalities
16,214 Fatalities from Run-Off-The-Road Crashes
740,000 Road Departure Injury Crashes
267 Crossover Head-On Fatal Collisions
Cable Median Barrier
Safe
Effective
Cost Efficient
Proven Results
Replaceable
What Is Cable Barrier …
Cable Median Barrier
Why Cable Median Barrier? And Why Now?
R E S U L T S
Cable Median Barrier
20 Reported Cable Median Barrier Impacts0 Penetrations – 0 Crossover Fatalities
First vehicle to impact cable barrier (March 2005)No Injuries 2001 2002 2003 2004 2005
Crossover Crashes
Fatalities
Cable Barrier Installed
(May 2005 thru April 2006)
Cable Median Barrier
Minimize Cross-Median Crashes
Lower Deflection Rates
Less Maintenance
Residual Safety Value
Lower Market Prices
Cable Median Barrier
“For every one fatal across median crash
there were 10 non-fatal across median
crashes.”
“Median Barriers in North Carolina,” AASHTO Subcommittee on Design, 2006
Cable Median Barrier
Fatalities
Fatal Crashes
1994-1998 1999-2003
Across-Median Crashes Decreased or Eliminated
Lives Saved
Millions in Crash Cost Savings
Cable Median Barrier
Generic Cable $8.33/Foot
High Tension Cable $12.23/Foot
W-Beam $13.65/Foot
Pre-Cast Concrete $24.64/Foot
Single Slope Concrete $44.94/Foot
Cast in Place Concrete $79.36/Foot
Issues & Concerns: Barrier Costs
Cable Median Barrier
Issues & Concerns: The Choices
SafenceTrinity Cable Safety Systems
(CASS)
Brifen Wire Rope Safety FenceGibraltar Cable Barrier
Nucor Marion U.S.High Tension
Cable Median Barrier
Issues & Concerns: Maintenance & Repair
Barrier Hits Per Mile
Cost Recovery
Frequency of Repair
Cable Downtime
Moving
Tension, Temperature & Elasticity
Cable Median Barrier
Issues & Concerns: Roadway Design
Cable Type
Cable Placement
Barrier Design
Transition from Cable toOther Types of Systems
Cable Median Barrier
Case Study: Utah Department of Transportation
Lessons Learned:
Compacted surfaceFacilitate winter maintenance and avoid erosionFoundation sockets flush to ground1:6 steepest slopeSystem hits effective
Cable Median Barrier
Case Study: Ohio
6:1 Slope
Socketed System
Cable Heights
High Tension System
10’ Offset from Ditch Centerline
Cable Median Barrier
Case Study: North Carolina
8’ Offset at 60’ Median Widths Cable Height
Design Specifications
Median Barrier Drawings
70’ Median Width or Less
500 Miles of Low Tension Barrier
14’ Designed Deflection
4’ Offset from Ditch Line
Cable Median Barrier
Case Study: Texas
High Tension Cable System
6:1 Slope
Standard Details and Specifications
Cable Barrier Behind W-Beam
10’ to 12’ Off Edgeline
Cable Median Barrier
Case Study: Washington
Cable Height
Pre-Cast Concrete Barrier
NCHRP 350 Test Level 3
High Tension and Low Tension
6:1 Slope and 10” Offset
70 Miles in 8 Counties
Cable Median Barrier
Issues & Concerns: Motorcycle Safety
Barrier Performance
Barrier Type Total Collisions Injury Collisions Fatal Collisions Percent Percent
Concrete 40 85% 7.5%
Beam Guardrail 65 81.5% 9.2%
Bridge Rail 10 80% 10%
Washington State Highways, 2003-2004
Cable Median Barrier
Resources Available: AASHTO TIG Web Site
Contact Information Challenges Roadway Design Issues Maintenance Issues Benefits & Evaluations System Threats
You’ll also find links to:
Lead States Team StudiesFHWA EvaluationTexas Transportation InstituteVendorsAnd more ….
Cable Median Barrier
Resources Available: The Lead States Team
North CarolinaKevin Lacy (919) 733-3915 [email protected] Hopkins (919) 715-7818 [email protected] Mayhew (919) 715-7818 [email protected] Troy (919) 733-5692 [email protected] Murphy (919) 755-3668 [email protected] Thomas (919) 250-4016 [email protected] Capps (919) 733-3725 [email protected]
WashingtonDick Albin (360) 705-7451 [email protected]
OhioDean Focke (614) 466-2847 [email protected]
UtahRob Clayton (801) 964-4521 [email protected]
TexasRory Meza (512) 416-2678 [email protected]
Cable Median Barrier
Resources Available: For the Media
Cable Median Barrier
Resources Available: Evaluations, Case Studies & More
Cable Median Barrier
Resources Available: To Learn More
Federal Highway Admininstration: http://www.safety.fhwa.dot.gov
Brifen U.S.A. http://www.brifenusa.com
Gibraltar http://gibraltartx.com
Nucor Steel Marion http://nsmarion.com
Safence http://www.safence.com
Trinity http://www.highwayguardrail.com
AASHTO TIG http://www.aashtotig.org