Cervical spine injuries during car collisions with three types of roadside barriers

Abstract

Traditional methods for assessing vehicle passenger safety in crash tests involving roadside barriers rely on safety indices derived from vehicle kinematic responses. However, this approach may not accurately capture the complex biomechanical stresses exerted on the human body during a collision, raising concerns about the validity and reliability of these indices in accurately evaluating passenger safety. This study investigates the effects of three different types of roadside barriers on vehicle passenger safety using three approaches: (1) assessing compliance with the EN1317 standard based on vehicle kinematics; (2) utilizing the Finite Element (FE) Human Body Model (HBM) dummy and Federal Motor Vehicle Safety Standards 208 criteria; and (3) conducting detailed examinations of cervical spine biomechanics. FE simulations, incorporating a biofidelic FE-HBM, are used to evaluate vehicle passenger safety under TB32 impact conditions as specified by the EN1317 standard. The findings reveal that while all barriers effectively contain and redirect the vehicle, the concrete barrier poses the highest risk of occupant injuries, with the highest safety indices and stress levels in the cervical spine, exceeding safe thresholds due to its high lateral stiffness. In contrast, the cable barrier provides the most favorable conditions for vehicle passengers, exhibiting the lowest stress levels and ensuring superior safety performance. The W-beam barrier demonstrates intermediate performance. The analysis also highlights the significance of the tension–flexion loading condition in passenger neck injuries. This condition accounts for 70% of the neck loading intensity for the concrete barrier and 90% for the cable and W-beam barriers, lasting the longest among all neck loading modes. While current safety standards indicate a low risk of occupant injury, detailed FE analysis and cervical spine stress values suggest potential neck injuries, especially with the concrete barrier. These findings emphasize the need to revise current safety standards to include more comprehensive biomechanical evaluations, potentially leading to enhanced road barrier designs and improved road safety standards.