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The use of high strength steel grades in automotive applications has been widely recorded. This is due largely to vehicle weight reduction programmes as well as increases in vehicle crash safety legislation. This represents the steel industry's response to the challenge that vehicle components manufactured from steel could get replaced with alternative materials, such as aluminium and polymers. Consequently, new high strength steel grades have been developed to offer credible alternatives. Recently, the UK government has released a new specification, BS EN 1317-1-2-3-4: Road Restraint Systems, to which all new safety barrier designs have to comply. However, much of this development and subsequent usage has been targeted at automotive manufacturers. Road safety barrier technology has not evolved in the same way when compared to vehicle technology. Therefore, a study has been undertaken to assess the outcome of using some of these novel high strength steel grades for the manufacture of road safety barrier components. Quasi-static and dynamic tensile testing at different velocities was undertaken. Representative connection coupons were used to understand the energy absorbing properties of a dual phase steel grade when compared to the current CMn steel grade. The present study presents some initial results as to the increased performance that could be gained from utilising new high strength steel grades for the production of road safety barrier systems.

The performance of road safety barrier connections is not directly linked to advances in vehicle technology. The UK government has recently released a new vehicle restraint systems specification that has resulted in the transfer of design responsibility to industrial safety barrier manufacturers. Road safety barrier connections utilise slotted holes that are perpendicular to the direction of the safety barrier beam profile. The bolt is significantly smaller than the slot and different performance outcomes can result from the positioning and preloading of the bolt with relation to the slotted hole.Finite element models have been constructed and validated using theoretical data as well as experimental data produced using a series of laboratory tests. The finite element model has been based on a standard test coupon that incorporates a full size safety barrier connection slot to industry standard dimensions.The laboratory results showed that the maximum force and displacement of the connections are comparable to the finite element model predictions. Comparisons made between the independent testing of safety barrier connections and the laboratory test coupons indicated that there was a good preliminary correlation between the computer model and the laboratory test coupons. Subsequently a simplified approach has been applied to the finite element modelling method with respect to connection movement mechanisms.