A new study from the University of Nebraska-Lincoln (UNL) argues that one of the mainstays of any drive should be altered. Guardrails could be risen from the current 31 to 36 inches and become much safer for that extra five inches.
Coming out of UNL's, (MRSF), which is funded by a consortium of midwestern states, the recommendations follow full-scale crash tests and extensive computer modeling. The paper reporting their findings has been published in the journal .
One of the difficulties in building out safety features for roads is that you have to try and accommodate as many sizes of vehicle as possible. This can get tricky with smaller vehicles, so the UNL team got two Kia Rios and several high-speed cameras and drove the cars into 34- and 36-inch guardrails at around 60 MPH.
Every guard rail system has a few ideal properties, according to a . You don't want guardrail components that could pierce the vehicle's cabin or sail into traffic. Guardrails should also keep vehicles from flipping, rolling or breaking through the barrier as well as limiting the acceleration that occupants endure during an impact. The 36-inch barrier prevented the Kias from breaking through and, according to computer simulations, reduce the odds of the pickup trucks mounting the guardrail or rolling over.
"We didn't see any instability in the vehicles" at 36 inches, Asadollahi Pajouh, a postdoctoral researcher with the MRSF. "That's what we want in our crash tests and our simulations."
However, in making the new guard rails, precision will be crucial. That's because while 36 inches is the safest you could make a guard rail, 37 inches could be deadly. That's the exact height where the Kias run the risk of becoming wedged beneath the rail, which poses fatal risks to occupants.
While crash test are the bread and butter of roadside safety tests, their expensive nature requires that computer simulations make up a lot of the work. Pajouh and her colleagues plan to conduct crash tests with pickup trucks prior to their final recommendations on guardrail height.