Modern Vehicles Spur Reevaluation of Highway Curve Design
As the automotive industry moves toward heavier and more technologically advanced vehicles, highways may need a makeover to accommodate these changes. A study led by the University of Mississippi is set to explore whether the current highway curve designs are suitable for today’s diverse vehicle fleet.
Electric vehicles (EVs), with their unique weight distribution due to heavy batteries typically located underneath the cabin, present new challenges and opportunities for road design. These changes, combined with advancements in tire technology, suspension systems, and electronic stability controls, influence how vehicles handle road curves.
Amir Molan, an assistant professor in civil engineering at Ole Miss, highlighted, “Changes in vehicle weight, weight distribution, tires and other vehicle technologies can affect how a vehicle behaves on a curve.” Molan is joined by graduate students Shaishav Acharya and Jawad Mehmood in conducting this research, funded by a $500,000 grant from the National Cooperative Highway Research Program.
This study will focus on the superelevation, or banking of curves, on American highways to see how it performs with modern vehicles. “When moving through a horizontal curve, various forces act on the vehicle, potentially causing skidding or rollovers,” commented Mehmood. “With advanced tires, pavements, and the rise of automated and electric vehicles, the dynamics of these forces have shifted.”
Electric vehicles tend to be heavier than their gas-powered counterparts due to the batteries. “The lower center of gravity could actually enhance stability,” said Acharya. “This differs from conventional vehicles, and current guidelines might not fully account for these factors.”
Despite the rise of modern vehicles, road designs must continue to accommodate older vehicles, Molan stated. The overarching goal is to ensure safer roads for all types of vehicles. “We need to ensure our recommendations are compatible with both the existing infrastructure and the vehicles currently in use,” Molan emphasized.
With some roads, like the Vegas Loop and the upcoming Music City Loop in Nashville, primarily serving electric vehicles, the study will explore specific considerations for such environments. “What guidance can we provide regarding speed or design to enhance safety?” Molan pondered.
Findings from this study could influence updates to the American Association of State Highway and Transportation Officials (AASHTO) Green Book, a crucial guide for highway design used globally. “It’s perhaps the most renowned road design guideline worldwide,” Molan noted. Acharya added, “Vehicles are evolving, and it’s crucial that our guidelines evolve with them.”
This investigation is part of the NCHRP project 15-85.
Top: Roadway curves originally designed for older vehicles are under review by an Ole Miss civil engineering team led by Amir Molan. Electric and autonomous vehicles, which have different centers of gravity than traditional cars, are part of this study. Photo illustration by Stefanie Goodwiller/University Marketing and Communications
Original Story at olemiss.edu