Finite element simulation and failure analysis of fixed bollard system according to the PAS 68:2013 standard

Proceedings of the Institution of Mechanical Engineers, Part D:

Ozcan

2022

Road restraint systems-RRS are passive safety designs installed on roadsides to ensure the safety of errant vehicle passengers as well as pedestrians. The adequacy of these systems is assessed through full-scale vehicle crash testing for which evaluation criteria are determined by standards such as EN1317. Recently the same RRS is crash tested two times with two different 900 kg passenger cars and test results varied significantly. After a failed crash test instead of modifying the barrier test vehicle was replaced and the same test was repeated. It was surprising to see that the failed RRS this time satisfied the EN1317 evaluation criteria. Despite the use of the same mass vehicle in the crash tests, the different results obtained were a source of motivation for investigating the inadequacy of EN1317. In this study, the adequacy of the 900 kg vehicle criteria used in the determination of the safety parameters in the EN1317-TB11 test was investigated by creating validated finite element-FE models. After the FE analysis it was concluded that test vehicle properties, such as vehicle mass and velocity provided in EN1317 are deemed to be insufficient and more explicit vehicle selection parameters, given in the study, are needed to provide safer and more uniform crash testing results.

Section: Numerical Results and Discussionmentioning

confidence: 97%

Section: Vehicles Typementioning

confidence: 99%

Criteria inadequacy of the vehicles used for the calculation of safety parameters in the EN1317-TB11 test

Proceedings of the Institution of Mechanical Engineers, Part D:

Ozcan

2022

“…According to Yumrutas et al [9], performance analysis of the newly developed hybrid barrier was made compared to the conventional roadside barriers, and it was stated that the developed hybrid barrier could be used as an alternative to the commonly used barriers. In the study for the development of bollard systems used to protect the infrastructure facilities used in the city [10], the weaknesses of the existing bollard systems were identified and suggestions were made for their improvement. In the study conducted by Yilmaz et al [11], the motorcyclist protection barrier system was optimized, as a result safer and more economical sections were obtained.…”

Section: Figure 1 -(A) Concrete Barriers (Rigid) (B) Steel Guardrails...mentioning

confidence: 99%

Finite Element Analysis and Investigation of Critical Impact Point of Steel Guardrails Affecting Safety and Structural Performance

Turkish Journal of Civil Engineering

2023

Self Cite

After the guardrails are designed, the structural adequacy and safety criteria are determined by the relevant standards and full-scale crash tests. One of the widely used standards is European Norm 1317 (EN1317). Guardrail systems generally consist of rails and posts. The guardrails are more rigid around the posts, which are mounted on the ground or embedded in soil at certain intervals. Therefore, it is important for driver/passenger and roadside safety to determine the most critical point in terms of structural and safety performance and design according to the most unfavorable situation. With this motivation, in this study, the effect of different impact points on the structural and safety performance of the H1W4 guardrail was investigated by finite element (FE) analysis. For this purpose, first of all, the finite element models of the H1W4-A system were calibrated and validated with real crash test data. Then, with the help of the validated models, analyses were completed for different impact points as 0.5, 1.0, 1.5 and 2.0 meters with a half-meter difference for the standard 2-meter post spacing. In the light of the measured safety parameters such as Acceleration Severity Index (ASI), Theoretical Head Impact Velocity (THIV) and structural performance criteria such as working width (W) and exit angle (α), the critical impact point for the guardrail was determined. Contrary to what is generally known, crashing vehicles into flexible points (0.5 and 1.0 m) rather than impacting rigid points (1.5 and 2.0 m) creates a more negative situation in crash tests.

“…Therefore, FE analyses have become an important tool to analyze roadside barriers with cost-effective solutions (Atahan and Cansiz 2005;Atahan 2006Atahan , 2010Atahan et al 2014). In this regard, LS-DYNA finite element simulation software that is used primarily in dynamic crashworthiness analysis was effectively applied in many studies (Wright and Ray 1996;Eskandarian et al 1997;Ray 1997;Plaxico et al 1998;Uddin and Hackett 1999;Atahan 2002Atahan , 2006Tiso et al 2002;Kirkpatrick et al 2003;Bligh et al 2004;Reid 2004;Whitworth et al 2004;Wu and Thomson 2004;Griškevičius et al 2007;Vesenjak et al 2007;Tabacu and Pandrea 2008;Štych 2010;Ferdous et al 2011;Amato et al 2013;Borovinšek et al 2013;Neuenhaus et al 2013;Mirdamadi 2014;Mojdeh 2015;Teng et al 2016;Yin et al 2016;Soltani et al 2017;Wu 2000, 2020;Baranowski and Damaziak 2021;Apak et al 2022) and also will be applied in this study. Pendulum crash tests have also been conducted widely in the literature to verify and validate the virtual simulation tests (Gatchell and Michie 1974;Bank and Gentry 2001;Frp et al 2001;Atahan et al 2002;Mitchell et al 2006;…”

Section: Virtual Testsmentioning

confidence: 99%

Renewable hybrid roadside barrier: Optimization of timber thickness

Yorur

Yumrutas

et al. 2022

BioRes

Researchers have recently focused on new and original roadside barriers that prioritize aesthetic, and environmental concerns by employing natural materials. In this study, the safety performance (Acceleration Severity Index (ASI), Theorical Head Impact Velocity (THIV)), structural performance (Working Width (W), Exit Angle (α)), and failure analysis (visual deformation) of a newly developed Renewable Hybrid Barrier (RHB) system at different timber thicknesses were tried to be determined by pendulum crash test and Finite Element (FE) models. The FE models were calibrated and validated based on pendulum crash test results, and then the most suitable timber thickness in terms of safety and structural performance was determined via FE analyses. The results revealed that as the timber thickness decreased, the safety parameters, such as ASI and THIV, decreased, thus the barrier safety increased. However, it was observed that the deflection and deformations in the barrier increased as the timber thickness decreased. In this sense, the safest and the most structurally durable barrier was determined through conducting virtual optimization tests. Studies on diversification of the usage areas of natural/renewable materials should be increased in the future.