Numerical simulation of roadside safety barrier for crashworthiness assessment

Abstract

Nowadays, even with modern traffic safety regulations, some high risk accidents still occur. Many fatal injuries or even death accidents occur to road users. The research of safety levels for all road users has been developed over the years. Roadside safety barrier is one of the systems that have been developed to reduce number of fatal injuries. In order to employ the suitable safety barrier at a referred location several test must be perform. Many of these tests only focused in a high velocity impact because it is considered that high speed impact can cause major injury to the occupant, damage to the safety barrier structure and also vehicle. Because of this consideration minor research has been perform for low vehicle velocity. However low velocity impact can also cause injuries to the occupants and damage to the vehicle and safety barrier structure. The objective of this study is to perform impact simulation on low vehicle velocity and analyze the occupant injury risks, safety barrier structure and concrete foundation failure criteria. The crash simulation is between W-beam type safety barrier to a light vehicle applied with three types of impact velocities (40, 60 and 80 m/hour). The situation model of the crash refers to a real road profile located at Jamin Ginting Street, Medan, Indonesia. The simulation models consist of four main parts that are roadside safety barrier, concrete foundation, light vehicle and the road. American Association of State Highway and Transportation Officials (AASHTO) specification was used to develop the safety barrier models. All the main parts were developed from CAD software then exported to Finite Element Analysis (FEA) software. The simulations are carried out using LS DYNA, commercial FEA software. The foundation of the W–Beam barrier and the occupant injury risks were analyzed. During the impact the maximum load that occurred at the foundation was below the allowable load. The Acceleration Severity Index (ASI) value of all impact velocities was still at the acceptable range.