The problem of black spots and black sections : how they are identified taking into account the varying functions of roads.

This paper recommends priority support for a programme to assess and eliminate black spots and sections from the road network in Romania, where the condition of the road network is not good and maintenance is insufficient to stop degradation. During the last five years the rate of road accidents has increased. Studies carried out by the author were based on investigation and simulated experiments on various road sections. On the basis of assessment of functional quality indices concerning road traffic virtual safety, situations are classified according to determination of the priority of virtual non-safety for black spots and sections, and assessment of virtual safety levels. Additional information obtained includes characterisation of the road sections by virtual risk of road events occurrence, annual virtual number of events and probable annual costs of elimination of black sections or spots. In the field of road technical design the definition and assessment of virtual safety indices allow a coherent approach of optimisation of the planning of maintenance, taking into account that optimisation requires a complex mathematical model. After the first generalised data gathering action the studies allowed the author to express proposals for realising the package of automatic calculation programmes for the development of a data bank, characterised by these functions: chronological storage of data concerning the intrinsic characteristics of the roads; assessment of the indices for the network, classification of the sections and black spots depending on their importance; assessment of the risks and probable accident rates; predictions, simulations and cost-profit analyses for working plans; dynamic self correction of the mathematical models following the future recording of traffic events.