Vehicle Security Barriers (VSBs) are frequently utilised in urban settings to defend against vehicular terrorist attacks. They may come in various forms, including bollards, street furniture and landscape features. The effectiveness of such barriers is usually assessed through a singular vehicle impact test, in accordance with various test standards and guidelines. The substantial cost of impact tests significantly restricts the amount of impact scenarios that can be analysed. Numerical simulation methods can substitute physical tests by virtually testing barriers. Various practical configurations can be assessed, such as different impact speeds, impact angles, and site conditions.
As stated in several VSB-related impact test standards, such as the new ISO 22343, soil conditions can significantly influence the performance of VSBs. Nevertheless, test standards frequently lack comprehensive guidance on how to deal with soil conditions. However, it is crucial to be aware of the mechanical properties of the soil, especially when dealing with numerical simulations of the interaction between the soil and the embedded barrier foundation.
This report investigates the relationship between soil conditions and the performance, underscores the importance of considering soil conditions during the VSB design, highlights the need for consistent soil assessments, and provides guidance for enhancing security in urban areas.
While numerical vehicle models of specific vehicle categories are already available and can be utilized, the focus is on a methodology for numerically modelling the surrounding soil domain. The critical role of the soil domain dimensions, the influence of the finite element size in the meshed soil domain, and the soil modelling strategies are investigated. The basics on the characteristics of coarse-grained soil is presented, which are usually used in traffic infrastructure such as roadways or walkways. Sensitivity studies further highlight the role of soil material properties, such as the angle of internal friction, the angle of dilatancy, the cohesion and the Young's modulus on the VSB response. Furthermore, the influence of impacting vehicle’s type on the VSB response is demonstrated, i.e., EU-truck type versus US-truck type.
While the primarily focus is on the soil conditions, the report also addresses the vital role of the surface courses of traffic infrastructure, such as asphalt surface courses. Furthermore, it discusses the interaction between the VSB-foundation and underground infrastructure, encompassing elements like sewers and gas networks.
This report contributes towards the goal of further using numerical simulations to assess the performance of vehicle security barriers. It demonstrates that numerical simulations can be a useful tool for studying variations in the soil type, drawing inspiration from practical applications, e.g., due to different traffic infrastructure constructions. The findings emphasize the need for soil-focused guidelines for the testing and installation of vehicle security barriers.
ANDRAE Matthias;
MARKOVIC Damijan;
SCHUMACHER Ralf;
KARLOS Vasileios;
LARCHER Martin;
2024-02-28
Publications Office of the European Union
JRC136541
978-92-68-12809-1 (online),
978-92-68-12808-4 (print),
1831-9424 (online),
1018-5593 (print),
EUR 31844 EN,
OP KJ-NA-31-844-EN-N (online),
OP KJ-NA-31-844-EN-C (print),
https://publications.jrc.ec.europa.eu/repository/handle/JRC136541,
10.2760/33565 (online),
10.2760/330343 (print),
