Long Heavy Vehicle Combinations (LHVCs) are an attractive alternative to Conventional Heavy Vehicle Combinations (CHVCs) in goods transportation because of reduction in fuel consumption, reduced costs and emissions. One major issue concerning LHVCs is their potential impacts on traffic safety that is the most controversial issue of LHVCs. Road safety performance of LHVCs depends on their technical features such as power train and braking systems capability, lateral dynamical stability, manoeuvrability and etc. By introducing LHVCs as a part of future transportation, there is a need to ensure that they are performing within specific boundary conditions. Defining proper technical characteristics, denoted as Performance Based Characteristics (PBCs) for LHVCs would assist to create operational requirements by which LHVCs will be allowed to operate in the road network with less negative road safety impacts. A comprehensive list of safety related PBCs is defined in (1). In this paper the test conditions and methods for each characteristic are specified and a set of heavy vehicle combinations (including European vehicle combinations, modular vehicle combinations and perspective modular vehicle combinations) are assessed and compared by using computer simulations. In addition, it is shown that by design parameter changes it is possible to improve the performance of a truck with double centre-axle trailers to perform almost similar as existing European conventional vehicle combinations like a truck and centre-axle trailer combination
