Nebraska experts weigh highway safety and electric vehicles

The Midwest Roadside Safety Facility (MwRSF) at the University of Nebraska-Lincoln has mobilized to answer the safety and military defense questions raised by the burgeoning number of electric vehicles (EV) on the nation’s roadways. 

In research sponsored by the U.S. Army Engineer Research and Development Center (ERDC) and partnered with Auburn University's Transportation Research Institute (led by Laurence Rilett, former Mid-America Transportation Center and Nebraska Transportation Center director), the Nebraska facility recently conducted a first-of-its-kind crash test of an EV pickup truck to better understand whether currently used guardrails and U.S. military protection measures against hostile vehicles are prepared for the growing number of EVs.

Thousands of fatalities result each year from more than 100,000 run-off-road crashes involving traffic infrastructure such as roadside barriers.

"There is some urgency to address this issue," said Cody Stolle, MwRSF assistant director. "As the percentage of EVs on the road increases, the proportion of run-off-road crashes involving EVs will increase as well."

A crash test performed on a guardrail on October 12, 2023 highlighted the concern. At 60 mph, the 7,000-plus-pound, 2022 Rivian R1T truck tore through the barrier with little reduction in speed. In a separate test conducted in September 2023, a 2018 Tesla Model 3 sedan lifted the guardrail and passed below it, coming to rest behind the barrier.

Additional crash tests are planned. Afterwards, transportation officials, defense experts and MwRSF researchers will collaborate to determine next steps to accommodate the anticipated changes in America's vehicle fleet.

"The U.S. Army Corps of Engineers mission is to deliver vital engineering solutions, in collaboration with our partners, to secure our nation, energize our economy, and reduce disaster risk," said Genevive Pezzola, a research civil engineer at ERDC.

"It is critical to conduct these EV baseline comparison tests to understand any potential risks to our nation. This work is the first necessary step towards ensuring that our nation's protection measures, such as roadside barrier systems and barriers to protect against hostile vehicles, are adapting to accommodate for the changing composition of the vehicle fleet."

The guardrail system that was tested features 12-gauge corrugated steel guardrail attached to 6-inch deep steel posts anchored to the rail with blockouts 8-to-12 inches thick. The top of the rail is located 31 inches above the road.

Designed as an inexpensive, high-performing barrier, the tested guardrail system, the Midwest Guardrail System or MGS, was developed at MwRSF in response to barrier ruptures and rollovers with older systems. The MGS has been tested with small cars that weigh up to 2,400 pounds and pickup trucks that weigh 5,000 pounds. Until now, little has been known about how the system will perform in crashes involving EVs, which typically weigh 20 percent to 50 percent more than gas-powered vehicles, with lower centers of gravity.

MwRSF research suggests that EVs are involved in run-off-road crashes at about the same rate and about the same speeds as gasoline vehicles. That would mean an EV crashing into a roadside barrier could have 20 percent to 50 percent more impact energy.

"It is going to be necessary to re-examine the designs of roadside barriers even beyond the EVs,"Stolle said. "It's a critical and timely need."

UNL has led several efforts to create next-generation barriers. Besides the MGS, the MwRSF research team, led by former director Dean Sicking and current director Ron Faller, also developed the Steel and Foam Energy-Reducing (SAFER) barrier, improving race car track safety and saving race car drivers' lives. The SAFER barrier was even installed in the Rose Bowl during an exhibition racing event.

Today's challenge is to again adapt roadside barriers to match the mix of heavier electric vehicles, lighter gasoline vehicles, taller SUVs and pickup trucks and smaller cars. Fulfilling the challenge requires collaboration with diverse backgrounds in defense, transportation, design, and crash safety.

"We can learn a lot from the evaluation of EV response to well-defined barrier systems," Pezzola said. "Through computational modeling and additional tests, we can understand the military and defense implications, with a focus on mitigation and control of hostile vehicles. The overarching goal of this work is to ensure the public's safety and enhance protection of the nation's infrastructure."

UNL's research will contribute to the ERDC's vision through testing, simulation and design. Industry partnerships - including Caresoft Global, which gave UNL researchers access to a critical database on current vehicles, including EVs, and Ansys' LS-DYNA program used with UNL's supercomputer system - will kickstart work on the next generation of roadside safety systems.

"We need to know as much as we can now because it takes time to design new systems, evaluate them and confirm those results with full-scale crash testing," Stolle said. "Then state departments of transportation around the country can begin the process of upgrading roadside barriers to new versions with more robustness.

"We'll use our collective century of experience in roadside safety design to make those changes quickly and save lives."