Abstract

Purpose: Enhancing road safety is a critical goal worldwide, necessitating the development of clear standards for road safety systems. This study focuses on lumbar spine (L-spine) compression injuries during collisions with concrete road safety barriers (RSBs). It aims to analyze internal forces during impact to understand L-spine injury biomechanics in such accidents. Methods: The research included a literature review, analyzing American guidelines and European standard EN1317. A normative TB41 crash test with a concrete RSB class H2/W5/B was conducted, followed by a finite element model creation and validation. Additionally, a TB32 test simulation with the same barrier and a 50th percentile female body model was performed to analyze L-spine displacements. These displacements were applied to a detailed L-spine model based on THUMS v.6.1, modified for validation test compliance. Results: Numerical models for the concrete RSB and L-spine were validated against experimental data. The TB41 crash test showed that connections between barrier segments experienced splitting failure, with a maximum dynamic compressive force of 350 kN and bending moments up to 130 kNm. The TB32 crash test indicated that vehicle collision energy dissipation caused the car to launch upwards and land along the barrier. This resulted in high internal forces in the L-spine, particularly in the L3 vertebra with a compressive force of about 2.7 kN and a bending moment of 39.5 Nm. Conclusions: The study observed splitting failure in the H2/W5/B concrete barrier during the TB41 test. Discrepancies were noted between the safety levels indicated by impact severity indices and those suggested by L-spine injury measures. These findings suggest a need to reevaluate the current standards for road safety systems, considering both barrier integrity and potential spinal injuries.

Author (1)