1200 New Jersey Ave., SE

 Washington, D.C. 20590

FHWA:HSST:WLongstreet:ms:x60087:2/1/11

File: s://directory folder/HSST/Longstreet/B- Free Standing F-Shaped 

Temporary Concrete Barrier System.dotx

cc: HSST (WLongstreet; JDewar) 

February 10, 2011 In Reply Refer To:

HSST/B-215

Ms. Karla A. Lechtenburg, MSME

Research Associate Engineer

Midwest Roadside Safety Facility

527 Nebraska Hall

Lincoln, NE 68588-0529

Dear Ms. Lechtenburg:

This letter is in response to your request for the Federal Highway Administration (FHWA) 

acceptance of a roadside safety system for use on the National Highway System (NHS).

Name of system: Free Standing F-Shaped Temporary Concrete Barrier System

Type of system: Temporary Barrier

Test Level: American Association of State Highway and Transportation 

Officials (AASHTO) Manual for Assessing Safety Hardware 

(MASH) Test Level 3 (TL-3)

Testing conducted by: Midwest Roadside Safety Facility (MwRSF)

Date of request: August 17, 2010

Date initially acknowledged: August 29, 2010

Task Force 13 Designator: SWC09 (same as existing)

You requested that we find this system acceptable for use on the NHS under the provisions of the

AASHTO MASH. 

Requirements 

Roadside safety devices should meet the guidelines contained in the MASH.

Decision

The following device was found acceptable, with details provided below:

• Free Standing F-Shaped Temporary Concrete Barrier System
2

Description

The test installation was 62.34-m (204.5 feet) in length and consisted of sixteen (16) 3,810-mm 

(12 feet 6 inches) long, F-shaped temporary concrete barriers placed on the concrete tarmac 

without any attachment between the barriers and the tarmac. The concrete used for the barriers 

consisted of Iowa’s Barrier Mix, with a minimum 28-day concrete compressive strength of 

34.5 MPa (5,000 psi). The minimum concrete cover varied at different positions of rebar in the 

barrier. Minimum concrete cover of 51 mm (2 inches) was used along the top of the vertical 

stirrup rebar and the bottom longitudinal rebar. Minimum concrete cover of 44 mm 

(1-3/4 inches) and 25 mm (1-inch) were used along the sides of the vertical stirrup rebar and at 

the rebar around the anchor bolt block, respectively. All steel reinforcement in the barrier was 

ASTM A615 Grade 60 rebar, except for the loop bars which were ASTM A706 Grade 60 rebar. 

Barrier reinforcement consisted of three (3) No. 5 and two (2) No. 4 longitudinal bars, twelve (12) 

No. 4 bars for the vertical stirrups, and six (6) No. 6 bars for the anchor bolt block reinforcement 

loops. Each of the five longitudinal rebar was 3.71 m (12 feet 2 inches) long. The vertical 

spacing of the lower, middle, and upper longitudinal bars were 165 mm (6-1/2 inches), 368 mm 

(14-1/2 inches), and 780 mm (29 1/8 inches) from the ground to their centers, respectively. The 

1,829-mm (72 inches) long, vertical stirrups were bent into the shape of the barrier with varied 

spacing longitudinally. The 889-mm (35 inches) long anchor bolt block loops were bent into a 

U-shape and were used to reinforce the anchor bolt area. The barriers used a pin and loop type 

connection comprised of two sets of rebar loops on each barrier interconnection. Each loop 

assembly was configured with three (3) ASTM A706 Grade 60 No. 6 bars that were bent into a 

loop shape. The vertical pin used in the connection consisted of a 32-mm (1-1/4 inches)

diameter x 711-mm (28 inches) long round bar composed of ASTM, A36 steel. The pin was held 

in place using one (1) 64-mm wide x 102-mm long x 13-mm thick (2-1/2 inches x 4 inches x 

1/2 inches) ASTM A36 steel plate with a 35-mm (1 3/8 inches) diameter hole centered on it. The 

plate was welded 64 mm (2-1/2 inches) below the top of the pin. A gap of 92 mm (3 5/8 inches) 

between the ends of two (2) consecutive barriers was formed from the result of pulling the 

connection taut. Design details are provided as enclosure to this correspondence.

Crash Testing

Physical crash test for TL-3 as per MASH requires that longitudinal barrier systems be subjected 

to the following two full-scale vehicle crash tests:

1. Test Designation 3-10. A 1,100-kg (2,425-lb) passenger car impacting at a nominal

 speed and angle of 100.0 km/h (62.1 mph) and 25 degrees, respectively.

2. Test Designation 3-11. A 2,270-kg (5,004-lb) pickup truck impacting at a nominal

 speed and angle of 100.0 km/h (62.1 mph) and 25 degrees, respectively.

Only test designation 3-11 was conducted for the free-standing temporary barrier system 

described within the description section of this correspondence. 

In addition, as per MwRSF email correspondence dated January 28, 2011 regarding test 

designation 3-10, no testing of the 1100C vehicle was conducted as part of the MASH testing of

the F-shape PCB because the small car test is considered less critical due to lower impact energy 

and deflection. Also, previous testing of safety shapes with small cars has historically proven 

successful.
3

Findings 

The analysis of the crash test results showed that the Free Standing F-Shaped Temporary 

Concrete Barrier System impacted with 2270P test vehicle as per MASH adequately contained 

and redirected the vehicle with controlled lateral displacements of the barrier system. There 

were neither detached elements nor fragments which neither showed potential for penetrating the 

occupant compartment nor presented undue hazard to other traffic. Deformations of, or intrusion 

into the occupant compartment that could have caused serious injury did not occur. The test 

vehicle did not penetrate nor ride over the temporary concrete barrier system and remained 

upright during and after the collision. Vehicle roll, pitch, and yaw angular displacements were 

noted, but they were deemed acceptable because they did not adversely influence occupant risk 

safety criteria nor cause rollover. After collision, the vehicle’s trajectory revealed minimum 

intrusion into adjacent traffic lanes. In addition, the vehicle exited the barrier within the exit 

box. Therefore, test designation 3-11 as conducted on the free-standing temporary concrete 

barrier system was determined to be acceptable according to the TL-3 safety performance criteria 

found in MASH. A physical crash test summary is included as enclosure to this correspondence.

In addition, the requested waiver of test designation 3-10 and reasoning as provided within this 

correspondence is also accepted.

Therefore, the system described in the requests 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 FHWA letters of acceptance:

• This acceptance is limited to the crashworthiness characteristics of the systems and does not 

cover their structural features, nor conformity with the Manual on Uniform Traffic Control 

Devices. 

• Any changes that may adversely influence the crashworthiness of the system will require a 

new acceptance letter. 

• Should the FHWA discover that the qualification testing was flawed, that in-service 

performance reveals unacceptable safety problems, or that the system being marketed is 

significantly different from the version that was crash tested, we reserve the right to modify 

or revoke our acceptance. 

• You will be expected to supply potential users with sufficient information on design and 

installation requirements to ensure proper performance. 

• You will be expected to certify to potential users that the hardware furnished has essentially 

the same chemistry, mechanical properties, and geometry as that submitted for acceptance, 

and that it will meet the crashworthiness requirements of the FHWA and the AASHTO 

MASH.

• To prevent misunderstanding by others, this letter of acceptance is designated as number 

B-215 and shall not be reproduced except in full. This letter and the test documentation upon 

which it is based are public information. All such letters and documentation may be reviewed 

at our office upon request.

• This acceptance letter shall not be construed as authorization or consent by the FHWA to use, 

manufacture, or sell any patented system for which the applicant is not the patent holder. 

The acceptance letter is limited to the crashworthiness characteristics of the candidate 
4

system, and the FHWA is neither prepared nor required to become involved in issues 

concerning patent law. Patent issues, if any, are to be resolved by the applicant. 

Sincerely,

Michael S. Griffith

Director, Office of Safety Technologies

Office of Safety 

Enclosures 
52

Figure A-1. Layout for Free-Standing Temporary Barriers (English)
53

Figure A-2. Temporary Barrier Design Details (English)
54

Figure A-3. Temporary Barrier Profile Details (English)
55

Figure A-4. Temporary Barrier Bill of Bars (English)
56

Figure A-5. Temporary Barrier Connection Details (English)
58

0.122 sec 0.216 sec 0.400 sec 0.498 sec 0.000 sec

! Test Agency . . . . . . . . . . . . . . . . . . . . . . MwRSF! Test Number . . . . . . . . . . . . . . . . . . . . . . 2214TB-2! Date . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10/12/04! NCHRP 350 Update Test Designation . . 3-11! Appurtenance . . . . . . . . . . . . . . . . . . . . . Free-Standing Temporary Barrier! Total Length . . . . . . . . . . . . . . . . . . . . . . 204 ft - 6 in.! Key Elements - Barrier

Description . . . . . . . . . . . . . . . . . . . F-Shape BarrierLength . . . . . . . . . . . . . . . . . . . . . . . 12 ft - 6 in.Base Width . . . . . . . . . . . . . . . . . . . 22.5 in.Height . . . . . . . . . . . . . . . . . . . . . . . 32 in.

! Type of Soil . . . . . . . . . . . . . . . . . . . . . . NA! Test Vehicle

Type/Designation . . . . . . . . . . . . . . 2270PMake and Model . . . . . . . . . . . . . . . 2002 Dodge Ram 1500 Quad Cab PickupCurb . . . . . . . . . . . . . . . . . . . . . . . . 5,035 lbsTest Inertial . . . . . . . . . . . . . . . . . . . 5,000 lbsGross Static . . . . . . . . . . . . . . . . . . . 5,000 lbs

! Impact Conditions

Speed . . . . . . . . . . . . . . . . . . . . . . . 61.9 mphAngle . . . . . . . . . . . . . . . . . . . . . . . 25.4 degreesImpact Location . . . . . . . . . . . . . . . 3 ft - ll.3125 in. upstream barriers 8 & 9 joint

! Exit Conditions

Speed . . . . . . . . . . . . . . . . . . . . . 44.9 mphAngle . . . . . . . . . . . . . . . . . . . . . 7.9 degreesExit Box Criterion . . . . . . . . . . . Pass

! Post-Impact Trajectory

Vehicle Stability . . . . . . . . . . . . . . . SatisfactoryStopping Distance .............. 244 ft - 10 in. downstream

4 ft - 0.5 in. laterally behind

! Occupant Impact Velocity (350 Update)

Longitudinal . . . . . . . . . . . . . . . . . . 17.00 ft/s < 39.4 ft/sLateral . . . . . . . . . . . . . . . . . . . . . . 17.28 ft/s < 39.4 ft/s

! Occupant Ridedown Deceleration (350 Update)

Longitudinal . . . . . . . . . . . . . . . . . . 7.17 Gs < 20 GsLateral . . . . . . . . . . . . . . . . . . . . . . 11.37 Gs < 20 Gs

! THIV (not required) . . . . . . . . . . . . . . . . 22.60 ft/s! PHD (not required) . . . . . . . . . . . . . . . . . 11.52 Gs! Test Article Damage . . . . . . . . . . . . . . . . Moderate! Test Article Deflections

Permanent Set . . . . . . . . . . . . . . . . . 73 in.Dynamic . . . . . . . . . . . . . . . . . . . . . 79.65 in.Working Width . . . . . . . . . . . . . . . . 102.2 in.

! Vehicle Damage . . . . . . . . . . . . . . . . . . . Moderate

VDS5 . . . . . . . . . . . . . . . . . . . . . . . . 11-LFQ-3CDC6 . . . . . . . . . . . . . . . . . . . . . . . 11-LYES4

Maximum Deformation . . . . . . . . . 4.25 in. at front floorpan

Figure B-1. Summary of Test Results and Sequential Photographs (English), Test 2214TB-2