Effect of permanent jersey-shaped concrete barrier height on heavy vehicle post-impact stability

Abstract

Jersey-shaped permanent concrete barriers are extensively used at narrow medians, bridge decks and at roadsides where lateral barrier deformations are not allowed. It is well documented that the crash performance of concrete barriers depends mainly on the barrier geometry, such as shape and top height. In most US applications, the height of jersey-shaped concrete barriers is 810 mm, whereas in Europe, concrete barriers as tall as 1000 mm are used. According to European EN1317 crash test guidelines, concrete barriers should demonstrate acceptable crash test performances against 10, 30 and 38 ton heavy vehicle impacts. In this paper, the effect of permanent jersey-shaped concrete barrier height on post-impact stability of 10 and 30 ton heavy vehicles is investigated. A versatile finite element program LS-DYNA capable of representing crash test behaviour of roadside safety hardware is used for the analysis. A total of five simulations, four with a 30 ton vehicle and one with a 10 ton vehicle, are performed. Permanent jersey-shaped barriers with 810, 950, 1000 and 1050 mm top heights are modelled and subjected to 30 ton vehicle impact. Only one simulation is performed on 810 mm tall barrier using 10 ton vehicle. Simulation results predict that a minimum of 1050 mm concrete barrier height is necessary to achieve post-impact stability for the 30 ton vehicle. For the 10 ton vehicle, a conventional 810 mm tall barrier is found to be adequate to provide stable vehicle redirection. As always, full-scale crash testing is recommended to verify the acceptability of simulation findings.