CMBTIGPPT

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A Focus Technology of the American Association
of State Highway and Transportation Officials
(AASHTO) Technology Implementation Group (TIG)
CABLE MEDIAN BARRIER Best Practices Guidelines
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Cable Median Barrier
Share Sponsor Technology Transfer Promote
Transportation Advancements Encourage
Implementation
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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
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Cable Median Barrier
What Is Cable Barrier
Safe Effective Cost Efficient Proven
Results Replaceable
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Cable Median Barrier
Why Cable Median Barrier? And Why Now?
R E S U L T S
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Cable Median Barrier
20 Reported Cable Median Barrier Impacts 0
Penetrations 0 Crossover Fatalities
(May 2005 thru April 2006)
Cable Barrier Installed
Fatalities
First vehicle to impact cable barrier (March
2005) No Injuries
Crossover Crashes
2001 2002 2003 2004 2005
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Cable Median Barrier
Minimize Cross-Median Crashes Lower Deflection
Rates Less Maintenance Residual Safety
Value Lower Market Prices
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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
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Cable Median Barrier
Across-Median Crashes Decreased or
Eliminated Lives Saved Millions in Crash Cost
Savings
Fatal Crashes
Fatalities
1994-1998 1999-2003
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Cable Median Barrier
Issues Concerns Barrier Costs
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
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Cable Median Barrier
Issues Concerns The Choices
Trinity Cable Safety Systems (CASS)
Safence
Nucor Marion U.S. High Tension
Gibraltar Cable Barrier
Brifen Wire Rope Safety Fence
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Cable Median Barrier
Issues Concerns Maintenance Repair
Barrier Hits Per Mile Cost Recovery Frequency
of Repair Cable Downtime Moving Tension,
Temperature Elasticity
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Cable Median Barrier
Issues Concerns Roadway Design
Cable Type Cable Placement Barrier
Design Transition from Cable to Other Types of
Systems
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Cable Median Barrier
Case Study Utah Department of Transportation

• Lessons Learned
• Compacted surface
• Facilitate winter maintenance and avoid erosion
• Foundation sockets flush to ground
• 16 steepest slope
• System hits effective

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Cable Median Barrier
Case Study Ohio
High Tension System 10 Offset from Ditch
Centerline
61 Slope Socketed System Cable Heights
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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
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Cable Median Barrier
Case Study Texas

• High Tension Cable System
• 61 Slope
• Standard Details and Specifications
• Cable Barrier Behind W-Beam
• 10 to 12 Off Edgeline

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Cable Median Barrier
Case Study Washington

• Cable Height
• Pre-Cast Concrete Barrier
• NCHRP 350 Test Level 3
• High Tension and Low Tension
• 61 Slope and 10 Offset
• 70 Miles in 8 Counties

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Cable Median Barrier
Issues Concerns Motorcycle Safety
Barrier Performance
Percent Percent
Barrier Type Total Collisions Injury
Collisions Fatal Collisions
Concrete 40 85
7.5 Beam Guardrail 65 81.5
9.2 Bridge Rail 10
80 10
Washington State Highways, 2003-2004
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Cable Median Barrier
Resources Available AASHTO TIG Web Site

• Contact Information
• Challenges
• Roadway Design Issues
• Maintenance Issues
• Benefits Evaluations
• System Threats
• Youll also find links to

Lead States Team Studies FHWA Evaluation Texas
Transportation Institute Vendors And more .
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Cable Median Barrier
Resources Available The Lead States Team
North Carolina Kevin Lacy (919)
733-3915 jklacy_at_dot.state.nc.us Terry
Hopkins [phone] thopkins_at_dot.state.nc.us
Brian Mayhew [phone] bmayhew_at_dot.state.nc.
us Shawn Troy [phone] story_at_dot.state.nc.
us Brian Murphy [phone] bgmurphy_at_dot.stat
e.nc.us Roger Thomas [phone] rthomas_at_dot.
state.nc.us Scott Capps (919)
733-3725 scapps_at_dot.state.nc.us Washington Dick
Albin [phone] albind_at_wsdot.wa.gov Ohio D
ean Focke [phone] dean.focke_at_dot.state.oh.
us Utah Rob Clayton [phone] robertclayto
n_at_utah.gov Texas Rory Meza (512)
416-2678 ameza_at_dot.state.tx.us
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Cable Median Barrier
Resources Available For the Media
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Cable Median Barrier
Resources Available Evaluations, Case Studies
More
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Cable Median Barrier
Resources Available To Learn More
AASHTO TIG http//www.aashtotig.org
Federal Highway Admininstration http//www.safety
.fhwa.dot.gov Brifen U.S.A. http//www.brifenu
sa.com Gibraltar http//gibraltartx.com Nucor
Steel Marion http//nsmarion.com Safence h
ttp//www.safence.com Trinity http//www.high
wayguardrail.com