TTI Research Supervisor:
Nauman Sheikh, P.E.
Texas Transportation Institute
Texas A&M University System
College Station, Texas 77843-3135
(979) 845-8955 [email protected]
Pooled Fund Technical Representative:
Paul B. Fossier, Jr., P.E.
Assistant Bridge Design Administrator
Bridge and Structural Design Section
Louisiana Dept. of Transportation & Development
1201 Capitol Access Road
P.O. Box 94245
Baton Rouge, LA 79084-9245
(225) 379-1323 [email protected]
In 2008, Texas Transportation Institute developed a pinned down anchored temporary concrete barrier system for use on concrete bridge decks and pavements. This F-shape barrier with pin-and-loop connections was anchored using steel pins that passed through inclined holes cast in the toe of the barrier, and continued a short distance into the underlying concrete pavement or deck. The objective of the research presented in this report was to extend the use of the existing pinned down anchored barrier design for placement on asphalt with minimum modifications to the barrier design.
By performing a series of dynamic subcomponent tests and full-scale impact simulation analyses, the researchers developed an appropriate anchoring design for pinning the barrier to asphalt. This design involves placing the barrier on a 4 inch thick asphalt pad and pinning it to the ground using three steel pins per barrier segment. The pins are 1.5 inches in diameter and pass through slotted holes cast into the toe of the barrier at an inclination of 40 degrees from the ground.
A 151-ft long installation was built for Manual for Assessing Safety Hardware (MASH) test level 3 (TL-3) testing. This installation was comprised of 12 pinned down barrier segments and was placed adjacent to a 1.5H:1V slope with a 1-foot lateral offset.
Anchored Barrier before MASH Test 3-11.
MASH test 3-11 was performed with a 2005 Dodge Ram 1500 pickup impacting the barrier at a nominal impact speed and angle of 62.2 mi/h and 25 degrees, respectively. The test vehicle was successfully contained and redirected by the pinned down anchored barrier system. The pinned down anchored barrier design was considered a pass according to MASH TL-3 criteria. Maximum dynamic and static deflections of the barrier system were 17.8 inches and 17 inches, respectively.