Finite Element Simulation of Passenger Car Impact with Three-Wave Steel Guardrail on Expressway

The most frequent outcomes of traffic collisions between vehicles and bridge guardrails are severe injury, damage to the vehicles, and compromised integrity of guardrails. Special element codes typically approximate guardrail deformations from impacts. However, the FEAs now provide a refined alternative way of modeling these dynamics of collision. This paper presents an FEA-based Wave Beam Guardrail, the FEA-wBG method, which reduces impact severity for enhanced safety on expressways. An assessment of various collision scenarios preceded this through running simulations of impacts with speed and angles taken to different limits using the LS-DYNA finite element solver. These simulations model real crash conditions, showing the energy absorption of guardrails and force distribution concerning time, enabling the engineers to predict structural deformation and assess guardrail effectiveness in mitigating the collision's severity and protecting vehicle occupants. Finite element analysis has been at the core of the research into the safety of roadsides for over thirty years. Explicit dynamic finite element analyses like LS-DYNA complement physical crash tests. The simulation failures point out the weakness in the design, hence that used in constructing stronger guardrail systems. The retested models show that the proposed FEA-wBG method correlates well with the physical test results by producing a match of 97.2% in crash indicators, 96.7% in head injury prediction, and also giving accurate results in energy, deformation, and force calculation. Its outcome has translated into improved vehicle containment, fewer injuries to occupants, and better-informed, safer roadside protection design of expressways.