Innovative Walls Protect Drivers

What is strong but flexible, bends but won’t break, absorbs shock without splintering and is easily fabricated? Welcome to the latest innovation in racetrack safety, R.A.C.E. (Restrictive Air Controls Energy) Wall™ impact barriers by North Carolina-based Safety Systems, Inc., (SSI). Developed for use at NASCAR racetracks and utilizing proprietary technology and materials such as TIVAR®, a polymeric material produced by Poly Hi Solidur, headquarted in Fort Wayne, Indiana. SSI researchers have engineered an impact barrier capable of reducing G-force by at least 40 percent during impact.

According to Tim Smith, Chairman of SSI, the patented barriers are designed to absorb the force of the impact and allow the vehicle to slide along the wall instead of stopping abruptly and then being thrown directly back into oncoming traffic. “Our goal was to develop a wall with an external surface that was so slick it allowed cars to slide along the face while the internal bladder dissipated the impact’s force,” Smith explained.

R.A.C.E. Wall barriers comprise two essential components – the face and the bladder. “The face material is key to how efficiently the bladder system dissipates impact energy,” Smith said. “The stiffer the face material, the broader the area to which the impact-energy travels in those first milliseconds of impact, and the broader the area, the less G-force the vehicle occupants experience.”

TIVAR was chosen to be an integral part of this patented technology for its superior physical properties – tough, impact-resistant, very abrasion-resistant and in particular, an extremely low coefficient of friction. The low coefficient of friction means that the external wall surface or face is extremely slick, which allows the car to slide along the surface of the wall – which is exactly what the designers had in mind. TIVAR’s other properties – impact and abrasion resistance – improves the impact absorbing ability of the wall so the force of the crash is dissipated throughout the wall.

The interior of the wall is a rubber and mesh bladder material constructed using proprietary techniques. Utilizing CFD (computational fluid dynamics) software through the North Carolina A&T State University, Department of Mechanical Engineering to analyze airflow, SSI has been able to optimize airflow in the air-apertures both inside and outside the bladder for better regulation of the air cushion.

Initial physical crash tests performed at MGA Research Corp. demonstrated that during a crash at 90 mph, G-forces were 40 percent less with the R.A.C.E. Wall than with other barriers currently in use at NASCAR tracks. Testing is currently being scheduled to determine the benefits of the technology at speeds higher than 140 mph.

SSI contracted with Altair Engineering to conduct computer-generated crash simulations and Data Point Labs provided FEA (Finite Element Analysis) testing. “We sought out companies that were recognized for the integrity of their test results as well as being familiar with the racing industry,” Smith said. “We knew we needed absolutely independent results in order for us and others to be confident that the safety issues we were addressing (impact and G-force) could be reduced through the use of our product.”

“We not only tested our R.A.C.E. Wall barrier, but we have also consistently tested a “replica” of another soft wall product that is currently installed in many NASCAR racetracks so that we have physical data to back-up the computer simulated data under identical crash scenarios,” Smith explained. “Based on the data, the R.A.C.E. Wall barrier performs better – and it is reusable, which provides a strong economic benefit for tracks that incorporate safewalls into their facilities.”

He added that unlike polystyrene barriers, the R.A.C.E. Wall barriers with TIVAR won’t disintegrate after impact, so not only are the walls reusable, there is no wall debris after a crash.

Smith and his colleagues are also exploring the use of R.A.C.E. Wall barriers on highways and interstates, particularly in high-risk, congested areas where the energy-absorbing capabilities of the walls could potentially save the lives of commuters, vacationers and their passengers.

“With just a little more tweaking, we feel we will have accomplished what we set out to do – make racetracks safer and transfer the safety technology to roadways used by everyday vehicles.”

For more information, contact Ron Denoo, Poly Hi Solidur, Inc., 2710 American Way, Fort Wayne, IN 46809, 260-479-4263, Fax: 260-478- 1074, E-mail: tivar@polyhisolidur.com, Web: www.polyhisolidur.com.