U.S. Department of Transportation
Federal Highway Administration
1200 New Jersey Avenue, SE
Washington, DC 20590
202-366-4000
U.S. Department of Transportation
Federal Highway Administration
1200 New Jersey Ave. S.E.
Washington, D.C. 20590
December 9, 2008
In Reply Refer To: HSSD/B-184
Mr. Rick Mauer
Outside National Sales Representative
Nucor Steel Marion Inc.
P.O. Box 837
Greenland, NH 03840
Dear Mr. Mauer:
This letter is in response to your request for Federal Highway Administration (FHWA) acceptance of a modification to a Nucor Steel Marion W-beam barrier for use on the National Highway System (NHS).
Name of system: | Nu-Cable System – Extended Hanging Hook |
---|---|
Type of system: | Cable Barrier |
Test Level: | NCHRP Report 350 TL-4 |
Testing conducted by: | Holmes Solutions of New Zealand |
Date of request: | July 25, 2006 |
You requested that we find this modified system acceptable for use on the NHS under the provisions of the National Cooperative Highway Research Program (NCHRP) Report 350 "Recommended Procedures for the Safety Performance Evaluation of Highway Features."
Requirements
Roadside safety systems should meet the guidelines contained in the NCHRP Report 350. FHWA Memorandum "ACTION: Identifying Acceptable Highway Safety Features" of July 25, 1997, provides further guidance on crash testing requirements of longitudinal barriers.
Description
The Test Level 4 (TL-4) Nu-Cable barrier system consists of four steel cables mounted on 4 pound/ft Nucor Steel Marion Rib-Bak u-channel posts. This system was found acceptable in the following FHWA Acceptance Letter:
Crash Testing
The Nucor Nu-Cable System consists of four 19-mm (3/4-inch) wire rope cables at heights of 380 mm, 640 mm, and two at 890 mm (15 inch, 25 inch, and 35 inch) above ground level. The lower two cables are attached using locking hook bolts which connect directly to the U-posts. The top two cables are supported by a top clip which engages with the top of the U-post section. The original hanging clip held the top two cables at the same height of 890 mm above the ground. Because these two cables are next to each other the barrier appears to have only 3 cables when viewed from a passing vehicle. Your present request is to revise the hanging clip by lowering one of the cables by 100 mm (4 inches.) This will separate the cables so that all four are visible. As the cable on the near-side of the post will remain at 890 mm there should be no change in performance of the barrier under TL-4 conditions.
Therefore, the Nucor Nu-Cable System with the revised hanging clip described above and detailed in the enclosed drawings is acceptable for use on the NHS under the range of conditions tested, when such use is acceptable to a highway agency.
Please note the following standard provisions that apply to the FHWA letters of acceptance:
Sincerely yours, David A. Nicol |