A Freeway Impact Attenuator is a traffic control or traffic accident impact absorbing device that will be deployed and replaced the conventional sand filled plastic buckets on the highway exits, junctions and temporary highway constructions. The rear support bracket for the temporary deployment to be replaced with concrete block to keep the unit from sliding.
The bumper and sliding tube move backwards and simultaneously the water in the cylinder get compressed while piston also moves backwards once impact force exerted to the bumper. The sliding tube and piston is interfaced through the clamp.
When the water pressure increases to the level that cylinder piston reaction force overcome the impact, sliding tube will stop prior to the end of cylinder full stroke.
Water level inside the tank will also increase and may over flow in some case is depending on the piston traveling in the cylinder.