Evaluation of 12 m Long Turned Down Guardrail End Terminal Using Full-Scale Crash Testing and Simulation

Abstract

The beginnings and ends of guardrail designs have the function of providing adequate anchorage for the rest of the system. They should also demonstrate crashworthy performance and should not pose any hazard for errant vehicles. In Europe, the ends of guardrail systems traditionally have incorporated turned down end terminals. Due to its low cost, Turkey also adopted turned down guardrail end terminal, and the majority of these designs are 12 meters long. Accident statistics clearly demonstrate that this particular end terminal poses safety risks for impacting vehicles. However, crash tests performed on the system showed that it worked satisfactorily for cars impacting at 80 kph. In this study, a detailed finite element analysis was performed on a 12 m long turned down guardrail end treatment to fully evaluate its crashworthiness. Data obtained from previously performed TT 2.1.80 and TT 4.2.80 crash tests were used to verify the fidelity of finite element models used in the study. Further simulations performed in accordance with EN1317 part 7 at 100 kph demonstrated unacceptable performance for the end terminal. Results of the study are summarized and recommendations are presented.

Analysis of Vehicle Collision on an Assembled Anti-Collision Guardrail

“…(1) The appropriate range for guardrail height should be determined according to the road grade. (2) The diameter or distance between steel strands should be adjusted to increase the displacement of the U-shaped base and to further reduce vehicle acceleration.…”

“…To protect the driver and passengers and to improve the guardrail collision performance, a series of studies using finite element simulation and on-site crash tests have been conducted. Ali O. Atahan performed a detailed finite element analysis on a 12 m long, downturned guardrail end treatment to fully evaluate its crashworthiness [ 2 ]. The response of a G4(1S) strong post steel w-beam guardrail system to pendulum impacts has been investigated [ 3 ].…”

Radial basis function surrogate model-based optimization of guardrail post embedment depth in different soil conditions

“…Studies on the numerical modeling of longitudinal barriers began in the 1960s and particularly after 2000, there were significant improvements in full-scale crash testing simulations of RRS, such as concrete barriers, steel guardrails, cable barriers, and crash cushions, or end terminals. 1–22 However, full-scale crash testing of engineered structures is both costly and time-consuming. With the development of accurate finite element (FE) models and algorithms, impact performance of RRS is more frequently assessed using LS-DYNA 23 (Livermore software open code three-dimensional (3D) FE program) and similar commercial FE programs.…”