What are crash cushions?
Crash cushions or impact attenuators are safety devices fixed to the end of concrete barriers and installed in front of other rigid structures such as columns, bridge supports, medians, islands and signs. Their purpose is to reduce the risk of serious injury to motorists who have lost control of their vehicle. Cars and trucks that impact a rigid road barrier head-on are at less risk of serious injury when a crash cushion is installed ahead of the barrier itself.
By absorbing the kinetic energy of an impact, crash cushions slow or redirect errant vehicles away from rigid hazards such as concrete road barriers.
These terminals are typically seen on many main roads throughout Australian as a forerunner to longitudinal road safety barriers. They allow the vehicle to be redirected in a controlled manner and dissipate some of its energy.
In addition to absorbing part of the impact of a collision, the crash cushions or terminals can also provide an anchor point for concrete barriers. Concrete barriers such as the DB80 are typically installed without ground anchoring. The modules are fixed to each other but not to the ground, therefore ensuring that they will flex as intended if impacted by a vehicle. However, most road authorities specify that concrete barriers typically need to be end anchored. A crash cushion provides the necessary fixing point.
Types of crash cushions
There are a series of different crash cushions and end treatments that are suitable for use with the Deltabloc DB80 concrete jersey barrier.
The Deltabloc DB80 is a TL-3 rated crash barrier, meaning in most circumstances, its accompanying crash cushion should be rated to the same level. Common crash cushions include the TAU-II and the Absorb 350.
ABSORB 350 PLASTIC TERMINAL
The Absorb 350 is a water-filled crash cushion that is approved to the NCHRP testing levels 1 and 2. This barrier is ideal for speed zones of 70km/hr and under. It is a non-redirective, gating crash cushion.
TAU II CRASH CUSHION
The Universal TAU-II Crash Cushion is a redirective, non-gating impact attenuator. It is designed to meet the requirements of NCHRP350 test levels TL-1, TL-2 and TL-3. It uses a series of crushable cartridges to absorb energy on impact. Furthermore, it is constructed from a steel skeleton surrounding collapsible HDPE bays. The TAU-II is typically used in speed zones in excess of 80 km/hr.
QUADGUARD CRASH CUSHION
The Quadguard is a redirective, non-gating crash cushion approved to NCHRP 350 TL-2 and TL-3. Similar to the TAU-II, it consists of a steel nose and energy-absorbing cartridges surrounded by a framework of steel panels.
This list is growing and changing. For the most up to date information, give our friendly team a call on 1300 788 476.
DB80 End Treatments
The Deltabloc range includes a sloped concrete end segment that can be used if your specifications and engineering advice require the installation of an end treatment.
The Deltabloc End Barrier serves as a transition to the nominated crash cushions. It is a standard DB80 safety barrier unit equipped with a special tension bar with an extended ‘Y’ profile on of the front ends.
Using Deltabloc End Barriers with the Absorb 350: The Deltabloc End Barrier should be anchored after the Absorb 350 anchor plate has been set into position. If installed first, the Absorb 350 base plate cannot be inserted under the end barrier.
Using Deltabloc End Barriers with the TAU-II: If using the TAU-II crash cushion, the Deltabloc End Barrier can be placed and anchored first, taking care to ensure enough room is left for the crash cushion.
Expert Assistance with Crash Cushions to suit Deltabloc barriers
Our specialist team of concrete and safety barrier experts can provide all the documentation you require including test reports and approvals for DB80 MASH approved concrete barriers, and assistance with crash cushions and end treatments.
Get in touch with our concrete barrier expert Ben Lorne today for more information.
Ben Lorne, Barrier Solutions Manager | firstname.lastname@example.org