March 27, 2002

> HSA-10/B97

Mr. Leo J. Yodock, III

Yodock Wall Company, Inc.

623 N.E. 5th Terrace

Ft. Lauderdale, FL 33304

Dear Mr. Yodock:

In your March 8 letter to Mr. Frederick Wright, former Program Manager
for the Safety Core Business Unit, you requested the Federal Highway
Administration's acceptance of two traffic barrier designs as National
Cooperative Highway Research Program (NCHRP) Report 350 test level 2
(TL-2) and test level 3 (TL-3) barriers, respectively. To support this
request, you also provided copies of three test reports prepared by the
Texas Transportation Institute and videotapes of the tests that were
conducted.

The first report, dated October 2001, is entitled "NCHRP Report 350 Test
2-11 of the 813 mm Tall Yodock Barrier Model 2001M, Energy Dispersement
Cell with Steel Tubing Side Rails Longitudinal Barrier." The test
installation consisted of 25 low-density polyethylene water-filled
barriers, each 1830-mm long, 813-mm tall, 457-mm wide at the base and
203-mm wide at the top. The individual units are connected at the ends
with polyethylene couplers and along the sides by 89 mm x 89 mm x 6.4 mm
structural steel tubes supported by steel brackets which extend through
two forklift holes in each unit. The steel side tubes are 1830-mm long
and spliced with 280-mm long 64 mm x 64 mm x 6.4 mm steel tubes using
two 19-mm diameter x 114-mm long Grade 8 hex head bolts. The centerline
height of the side rails was 596 mm. These design details are shown on
Enclosure 1. The results of test 2-11, a pickup truck impacting at 68.5
km/h and 24.0 degrees approximately 14 m from the upstream end of the
test installation, are summarized in Enclosure 2. All NCHRP Report 350
evaluation criteria were met. Barrier deflection under the stated impact
conditions was reported to be 3.68 m and the truck stopped in contact
with the barrier.

The second report, also dated October 2001, is entitled "NCHRP Report
350 Test 3-11 of the Yodock Barrier Model 2001, Energy Dispersement Cell
with Steel Tubing Side Rails for Longitudinal Barrier." The Model 2001
is similar in design to the 2001M model, but is larger, being 1170-mm
tall, 610-mm wide at the base, and 280-mm wide at the top. These units
were connected along each side by the same size steel tubes as described
above, but the centerline height of these rails was increased to 706 mm.
Enclosure 3 shows these and other design details. The results of test
3-11 are summarized in Enclosure 4. All appropriate evaluation criteria
were met, although the occupant impact velocity was near the upper
limit. Again, the truck was stopped in contact with the barrier. Dynamic
deflection was reported to be 4.28 meters, with the impact point
approximately 14 m from the upstream end of the 45 m-long test
installation.

The third report, dated February 2002, is entitled "NCHRP Report 350
Test 3-10 of the Yodock Barrier Model 2001, Energy Dispersement Cell
with Steel Tubing Side Rails for Longitudinal Barrier," and describes
the test with the 820-kg car into the taller Model 2001 design.
Enclosure 5 summarizes the results of this 97.7 km/h test.

Based on staff review of the information you provided, I agree that the
Model 2001M Longitudinal Barrier meets Report 350 evaluation criteria at
test level 2 (TL-2), and that the Model 2001 Longitudinal Barrier meets
test level 3 (TL-3) criteria. Either design may be used as a temporary
barrier on the National Highway System (NHS) when deemed appropriate by
the contracting authority. This acceptance is based on the crash
performance of your barriers and is not meant to address installation,
maintenance or repair of the barriers. It also assumes that any barrier
supplied for use on the NHS is identical in dimensions and material
specifications to the tested barrier. Since this product is proprietary,
the provisions of Section 635.411 of Title 23, Code of Federal
Regulations, are applicable.

Sincerely yours,

(original signed by David M. Smith)

> *for* A . George Ostensen
>
> Program Manager, Safety

5 Enclosures