Ever Hear of "Rebounding" Bollards?

All images courtesy: Impact Recovery Systems

It's important to know all your options when thinking about how to better protect your storefront from vehicle intrusions. Bollards represent one approach. They come in different sizes and types. Kenneth Parrott, senior project engineer at San Antonio, Texas-based Impact Recovery Systems, talks with me here about “rebounding bollards.” [Note: This post is not an endorsement of any company or type of vehicle barrier. It is offered purely for educational purposes. Always do your own research when considering the appropriate protection solutions for your storefront.]

Mark: What are rebounding bollards and how do they work?

Ken: “Rebounding bollards are a newer type of bollard that, as the name implies, rebounds after being impacted. Some will give way completely and allow a vehicle to run over the bollard, while others provide resistance to the vehicle. Our SlowStop Bollards are made of steel with an elastomer hidden in the base. When a vehicle impacts the bollard, the post and elastomer act together to absorb the energy to stop the vehicle, then rebound to an upright position. This reduces damage to the vehicle, bollard, and foundations, and also reduces the chance of injury to passengers.”

Mark: At what vehicle speeds are rebounding bollards most effective?
Ken: “In general, they are used at lower speeds from 0 to 10 mph. We have bollards from 3” to 6” in diameter that vary in their stopping power, which depends on the expected weight of the vehicle as well as the speed. For a typical 4,000 pound car or light truck, our 4” bollard would absorb up to 4 mph, and our 6” up to 8 mph. Multiple bollards, such as in a picket fence arrangement, work together to increase stopping power. You can find tables that show energy absorption capabilities here.”

Mark: In what types of specific locations/applications do rebounding bollards work best?
Ken: “I would recommend SlowStop Bollards for a storefront that doesn’t have direct access to the public street where vehicles might veer off at a high speed. If your parking lot is protected and lower speeds are expected, steel rebounding bollards are a great choice to reduce maintenance and damage from nuisance impacts.”

Mark: Do rebounding bollards require periodic maintenance of any type to ensure their effectiveness and longevity?

Ken: “They do not require any maintenance to maintain their effectiveness outside of periodic inspection for damage. In fact, one of the main reasons to consider them is that nuisance impacts will not damage the bollard and tear your concrete over time. Bollard covers can be used to eliminate occasional re-painting.”

Mark: Generally speaking, how do rebounding bollards compare to other bollard types on cost?
Ken: “The bollards themselves are more expensive than simply buying steel pipe; however, installation costs can be greatly reduced because they are surface mounted. Because they are sold as a system, they are usually pre-pained and come with all necessary hardware such as anchors. Long-term costs can also be reduced due to lower maintenance and replacement costs.”

Mark: Thanks for this information, Ken. One more time…where can people reach you if they have questions?
Ken: “They can contact me right here at Impact Recovery Systems.”

Editor's Note: For general information about various types and applications of bollards, visit the Whole Building Design Guide primer on bollards from the National Institute of Building Sciences.