KNOXVILLE (WATE) – After four deaths in 2016 were linked to a specific guardrail system, the Southeast Transportation Center at UT is sharing its insight into how the systems are suppose to operate.Previous story:4 Tennessee deaths in 2016 linked to guardrail system
Director of the Southeast Transportation Center, Dr. Stephen Richards, says the hardest part of a guardrail to design is the end treatment.
“We want the system to be able to restrain vehicles but we want to make them break away or in some way reduce the energy possessed by that fast moving vehicle and that’s just a very complicated engineering task,” said Richards.
According to the transportation center, every guardrail system is different, leaving some end terminals to collapse when hit.
However, before a guardrail is ever installed, it’s tested on six different levels with cars going up to 65 miles per hour.
“Some of those work for low speed collisions, some are more intended for medium speed impacts or high speed impacts. Having said that, there really is no guardrail that will work properly with very very high speeds,” said Richards.
The center says an end treatment to a guardrail is not supposed to penetrate a car, but Dr. Richards adds, “At some speeds that may be totally unpreventable.”
Every situation is different and so part of the design formula requires properly installing equipment so that it works safely.
“The slope of the land, the condition of the soil posts are embedded in, there are a number of factors. We have a standard test procedure but we can’t account for every single different condition we find out in the field,” added Dr. Richards.
While no design is perfect, engineers say this equipment is one of many tools used to protect drivers.
“Guardrails and guardrail end treatments are not anything for the public to panic over, just recognize it’s not a perfect engineering system,” said Dr. Richards.
TDOT has now accepted new stringent safety guidelines which were not supposed to be accepted nationally until 2019.
If you would like to take a look at the MASH safety guidelines, you can visit the Federal Highway Administration’s website by clicking here.