Mr. Barry D. Stephens, P.E. 

 Sr. Vice President Engineering 

 Energy Absorption Systems, Incorporated 

 3617 Cincinnati Avenue 

 Rocklin, California 95765 

 Dear Mr. Stephens: 

In my February 14 acceptance letter (HSA-10/B-134) for the Vulcan Barrier, I noted that 

additional information would be needed before the Vulcan could be deemed crashworthy and 

acceptable for use in bidirectional applications when connected to a rigid crash cushion or 

concrete barrier. Staff members had expressed concern about potential pocketing and/or 

snagging of vehicles impacting the freestanding Vulcan units immediately downstream from a 

rigid connection point. 

In late September, you provided members of my staff data from a reverse direction crash test 

you ran to address the above concern. The tested transition was designed to connect 

freestanding Vulcan Barrier units to an anchored QuadGuard CZ. The test results for the 

National Cooperative Highway Research Program (NCHRP) Report 350, Test 3-21 were 

supplied with your transmittal in the form of a crash test video, a 1-page test summary 

(Enclosure 1), and before/after photographs. The transition design consisted of a galvanized 

steel weldment measuring 2.03-m long, 0.8-m high and a variable width that matches the 

Vulcan Barrier shape to a .61-m wide QuadGuard CZ System (Enclosure 2). The transition 

incorporates a lower steel mounting plate measuring 9.5-mm thick x 1.07-m wide x 1.22-m 

long with twelve (12) mounting holes for anchoring the transition to a rigid foundation. For 

this crash test, four (4) unanchored Vulcan segments were pinned together and the upstream 

end was pinned to an anchored QuadGuard backup to provide tension to the unanchored 

Vulcan segments. The downstream end of the unanchored Vulcan was attached to the new 

transition that was, in turn, attached to a 6-bay, .61-m wide QuadGuard CZ backup. The 

targeted impact point was the connection between the unanchored Vulcan segment and the new 

transition. The 2000P vehicle was contained and redirected and the reported occupant risk 

values were considered acceptable. However, there remained some concern that field 

installations would be far longer than the test installation, resulting in greater barrier deflection 

and consequently, more pocketing in the transition area. 

400 Seventh St., S.W. 

Washington, D.C. 20590

In Reply Refer To: HSA-10/B-134A

November 17, 2005 
2

To mitigate our concern about pocketing, you submitted with your November 8 letter, a 

modified Vulcan design that incorporates additional anchoring on the impact side of the three 

Vulcan sections immediately upstream from the transition (Enclosure 3). Your design 

gradually increases the number of anchors per section on the approach to the transition. This 

increase in anchors provides gradual stiffening similar to that which has been successfully 

tested with precast concrete barrier segments connected to a rigid concrete bridge railing. 

Based upon the submitted test results and your Vulcan anchoring improvement, I agree that the 

proposed transition between Vulcan Barrier and anchored QuadGuard CZ Systems meets the 

NCHRP Report 350 TL-3 evaluation criteria and may be used on the National Highway 

System as a transition between these devices in bidirectional applications. I also agree that the 

results of the submitted test and the addition of anchors to the Vulcan units adjacent to the 

barrier support the acceptance of your transition between Vulcan and Concrete Median Barrier 

(CMB) when the Vulcan-to-CMB transition piece (Enclosure 4) is used. 

Please note also that the standard provisions for the Federal Highway Administration letters of 

acceptance noted on my original Vulcan acceptance letter remain applicable to this transition 

design.

Sincerely yours, 

 

 /original signed by George Ed Rice, Jr./ 

 ~for~ 

John R. Baxter, P.E. 

 Director, Office of Safety Design 

Office of Safety 

4 Enclosures 
Vulcan Transition Crash Test Results - 1 of 1

 Summary of Results - Vulcan Barrier Transition Test 01-8430-004

The results of this report relate only to the Vulcan Barrier Transition to QuadGuard configuration tested. This report may not be reproduced except in

full, without the prior written approval of E-TECH Testing Services, Inc. Prepared by: John F. LaTurner, P.E. - Manager. Report 267 - Issued 8/31/05 Exit conditions Speed (km/h) ........................................

Angle (deg - veh. c.g.) ..........................

Occupant Risk Values Impact Velocity (m/s) x-direction ....................................

y-direction ....................................

Ridedown Acceleration (g's) x-direction ....................................

y-direction ....................................

European Committee for Normalization (

THIV (km/h) .........................................PHD (g's) ..............................................ASI .......................................................

Test Article Deflections (m) Dynamic ...............................................

Permanent............................................

Vehicle Damage (Primary Impact) Exterior VDS ...............................................

CDC ..............................................

Interior VCDI .............................................

Maximum Deformation (mm) ...

Post-Impact Vehicular Behavior (deg - rat

Maximum Roll Angle .........................Maximum Pitch Angle ........................Maximum Yaw Angle .........................

t = 0.090 sec t = 0.180 sec t = 0.270 sec t = 0.360 sec 

General Information

Test Agency ............................................................. E-TECH Testing Services, Inc.Test Designation .................................................... NCHRP 350 Test 3-21Test No. ................................................................... 01-8430-004Date .......................................................................... 8/29/05

Test Article

Type ......................................................................... VulcanTM Barrier Transition

.......................................................................... to QuadGuard QZ2406Y Crash.......................................................................... Cushion, Transition 2030 mm x.......................................................................... 800 mm x 610 mm (L x H x W)

Installation Length ................................................ (4) Vulcan segments 16.5 m overall

.......................................................................... length w/o Transition and Crash.......................................................................... Cushion end ancorage

Material and key elements ................................... AASHTO M180 galvanized steel

.......................................................................... panels, ASTM A53 Pins, and A36.......................................................................... other

Foundation Type and Anchorage ................................. Concrete, (12) 19 mm x 165 mm

.......................................................................... ASTM A193 B7 studs, MP-3.......................................................................... Anchoirng System

Test Vehicle

Type ......................................................................... Production ModelDesignation ............................................................. 2000PModel ....................................................................... 1989 Chevrolet C2500 PickupMass (kg)

Curb ................................................................. 1988Test inertial .................................................... 1989Dummy ............................................................ N/AGross ................................................................ 1989

Impact Conditions

Speed (km/h) ........................................................... 99.7Angle (deg) .............................................................. 25Impact Severity (kJ) ............................................... 136.1

t = 0.000 sec

* Primary accelerometers subjected to significan

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