Federal Highway Administration
1200 New Jersey Ave. S.E.
Washington, D.C. 20590
January 26, 2009
In Reply Refer To: HSSD/LS-68
Mr. John F. Boozer III, P.E.
Shakespeare Composite Structures
19845 US Highway 76
Newberry, SC 29108
Dear Mr. Boozer:
This letter is in response to your request for the Federal Highway Administration (FHWA) acceptance of roadside safety devices for use on the National Highway System (NHS).
|Name of devices:||Shakespeare decorative poles (14)|
|Type of device:||Luminaire Support|
|Test Level:||Test Level 3|
|Testing conducted by:||Texas Transportation Institute|
|Date of request:||January 20, 2009|
|Date of follow-up:||January 27, 2009|
|Series: Name, Base Diameter (inches)||Series, Name, Base Diameter (inches)|
|AA15: Adams, 15||AM20: Madison, 20|
|AAN19: Anaheim, 19||AMB18: Monterey, 18|
|ABO19: Boise, 19||ASB10: Steamboat, 10|
|ACH9: Charleston, 9||AP13: Washington, 13|
|APB17: Pittsburg, 17||AP17: Washington, 17|
|AJ20: Jefferson, 20||AP20: Washington, 20|
|AM17: Madison, 17||AP24: Washington, 24|
You requested that we find these 14 devices 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.”
Roadside safety devices should meet the guidelines contained in the NCHRP Report 350, "Recommended Procedures for the Safety Performance Evaluation of Highway Features". The FHWA memorandum “ACTION: Identifying Acceptable Highway Safety Features” of July 25, 1997, provides further guidance on crash testing requirements of luminaire supports.
From the 14 devices listed above to be considered for acceptance, the Shakespeare AP20 luminaire support was determined to be reasonably representative of this product series. This product series of decorative luminaire supports conforms to the general construction details enclosed as a reference. Two AP20 decorative luminaire supports were tested and evaluated for crashworthy performance at the Texas Transportation Institute (TTI) outdoor pendulum testing facility. The weight of the pole base was 111 pounds and the round light fixture was 22 pounds, totaling a weight of 133 pounds. The pole base is a 20-inch diameter fiberglass reinforced composite with a 7-inch diameter hole at the center to accommodate wiring. For the first test, the base was attached to a rigid mounting plate with 3/4-inch bolts and standard 3/4-inch round washers. For the second test, the base was attached with 3/4-inch bolts and standard 3/4-inch round washers and shop made 1/8-inch by 2-inch by 2-inch washers. In the first test, the hand hole was placed to the opposite side of impact and for the second test it was placed on the impact side. Drawings of the AP20 support are enclosed.
Your company’s decorative lighting pole was tested at TTI’s outdoor pendulum testing facility, as a surrogate for full-scale crash testing. The pendulum bogie was built according the specifications of the Federal Outdoor Impact Laboratory's pendulum, and the frontal crush of the aluminum honeycomb nose of the bogie simulated the crush of an actual vehicle. Tests with pendulums are acceptable for most breakaway supports, exceptions being base bending or yielding supports.
Two low speed pendulum tests were conducted on Shakespeare’s AP20 decorative luminaire support. Summaries of the two test results are enclosed. The tested AP20 decorative luminaire support met the NCHRP Report 350 occupant risk criteria. In addition, TTI extrapolated the high-speed performance of the AP20 luminaire support from the low speed pendulum tests. The test articles appear to perform appropriately to make such high-speed extrapolations. The high-speed extrapolations yield lower change in velocity values than the paired low speed pendulum test.
In the two tests with the AP20 decorative luminaire supports, the base separated from the ground and the lighting pole separated from the decorative base section. The base fractured at ground line and this performance satisfies the FHWA limit of maximum 3.9 inch stub height remaining after a support breaks away.
In summary, the Shakespeare series of decorative luminaire supports listed above, including the AP20 support, meet the appropriate evaluation criteria for NCHRP 350 Test Level 3. Installations should include breakaway wiring connections that will not interfere with the crashworthy performance of these devices. These devices may be used at all appropriate locations on the NHS when selected by the contracting authority, subject to the provisions of Title 23, Code of Federal Regulations, Section 635.411 as they pertain to proprietary products.
Please note the following standard provisions that apply to the FHWA letters of acceptance:
David A. Nicol
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