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Department > 400 Seventh St.. S.W
ore aeereten Washington, D.C. 20590

Federal Highway April 9, 1996
Administration
Refer to: HNG-14

Mr. Roger C. Kellison
President

Kelken Construction Systems
436 Cerrillos Road

Suite A

Santa Fe, New Mexico 87501

Dear Mr. Kellison:

Your March 4 letter to Mr. James H. Hatton requested the Federal
Highway Administration's (FHWA) acceptance of a precast concrete
F-shape barrier and proprietary anchorage system that attaches
the barrier to a bridge deck with grouted, high strength bolts.
In support of your request, you referenced a 1988 crash test into
a precast New Jersey shaped profile that was similarly anchored.
In that test, an 18,000-pound (8000-kilogram) single-unit truck
impacted the test barrier at approximately 50 mph (80 km/h) and
15 degrees. The barrier consisted of 15-foot (4750-mm) and
20-foot (6100-mm) lengths of the New Jersey barrier, each having
a base width of 19 inches (500 mm) and a height of 34 inches

(860 mm). Each segment was bolted to a simulated bridge deck
with 1-inch (25-mm) diameter high-strength Kelibond anchors on
2-foot (610-mm) centers, and there was no connection between
adjacent segments. This installation met the evaluation
criteria for a PL-2 railing, as defined in the 1989 AASHTO "Guide
Specifications for Bridge Railings."

Since the 34.5-inch (880-mm) tall F-shaped barrier for which you
requested FHWA acceptance has the same base width as the tested
design, 20-foot (6100-mm) long segments, and added reinforcing
steel across the joints to provide barrier continuity, we will
accept the F-shape shown in Enclosure 1 as a PL-2 barrier (and
consequently, as a NCHRP Report 350 Test Level 4 barrier) without
additional testing. As requested, we will also accept minor
variations in cross section if an analysis similar to the

July 1995 analysis by Mr. Maurice E. Bronstad that you included
with your request is done to determine if a closer bolt spacing
or additional barrier reinforcement is needed. We note that the
crash test on the New Jersey shape did not test the open joint
between barrier segments. While Mr. Bronstad's analysis
indicates the design is adequate, it also shows that the segment
ends are the weakest points in the system. Therefore, analysis
of changes to the barrier cross section must include a check on
the adequacy of the segment ends. In all cases, the bridge deck
design must also be checked to ensure that it can carry the
dynamic. loads resulting from vehicle impacts.


‘

2

Our acceptance is limited to F-shape concrete barriers that are
approximately 34.5 inches (880 mm) high since no tests have been
run on the taller 42.5-inch (1080-mm) precast, bolted system for
which you also requested acceptance, nor did you include an
engineering analysis of the taller barrier. The height of the
taller F-shape implies a PL-3 or NCHRP Report 350 Test Level 5
capability and thus a much different loading requirement.

Because your deck anchoring system is proprietary, its use on
Federal-aid highway projects, except exempt, non-National Highway
System projects, is subject to the conditions set forth in

Title 23, Code of Federal Regulations, Section 635.411, a copy of
which is Enclosure 2.

A copy of this letter will be sent to FHWA field offices for
information. Any questions should be directed to Mr. Richard
Powers at (202) 366-1320.

Sincerely yours,

Seppo I. Sillan, Acting Chief,
Federal-Aid and Design Division

2 Enclosures

Federal Highway Administration

HNG~14: RPowers: 366-1320:gm: 4-5-96:KELLISON
copies to:

HPD-1 HNG-1 HNG-10 HNG-14

Reader, 3128 File, 3128

RAs HFL HHS~10 HSR-20 HNG-20

Supplement to Geometric and Roadside Design Acceptance Letter B-5