Currently the J-J Hooks connections are approved for use with either the Jersey shape or the F-Shape with a 24" wide base under NCHRP 350, Level 3 and accepted by the FHWA on all federal aid projects. Some states have modified the standard dimensions of Jersey and F shape barriers, making precast barriers profiles in those states unique.
J-J Hooks concrete barriers are available in 10-foot, 12-foot, and 20-foot sections. 20-foot (6.1m) sections are approved with additional reinforcing. Transition Sections, Bridge Barriers, and other special designs available in some locations.
This design, known as the "New Jersey Type" or “Jersey Walls”, was developed by the New Jersey State Highway Dept. This barrier type has the ability to:
- Absorb the impact of a moving vehicle.
- Slow down the impacting vehicle quickly.
- Guide the vehicle back into its original line of travel while the operator retains control depending on impacting angle of vehicle.
These characteristics are the result of the following primary features:
- A large mass of reinforced concrete that absorbs impact and resists penetration through a controlled deflection of the barrier.
- A gently sloped ramp, which tends to raise the impacting vehicle. Contact with the undercarriage causes the vehicle to slow down rapidly, while being returned safely to its original line of travel.
Naturally, as with any other type of barrier, some vehicular damage can be expected as a result of a vehicle/barrier collision. This fact has led to much research on various profiles.
The F-Shape is a new generation of the safety shape that is intended to further limit vehicle damage. The lower sloped face redirects vehicles under low-impact conditions. During moderate to severe impacts, some energy is dissipated when the vehicle is lifted off the pavement. The F-Shape reduces this lift, which promotes better vehicle stability while maintaining vehicle redirection. In crash tests, the F-Shape has proven to be more successful in preventing rollover of smaller vehicles. The F-Shape has been found to be more effective overall than the Jersey Shape barrier.Request Free Quote