A rational approach to the problem of the choice of the safety road barriers, through valuation of the total costs.

This paper presents a rational solution to the problem of the choice of safety road barriers, through valuation of the total costs based on a statistical and probabilistic approach. The necessary parameters are: a) cost of construction and installation of barrier b) yearly number of collisions between vehicle and barrier c) probability of the different velocity ranges d) probability of the different impact angles e) social economical cost of the accidents f) costs of the human injuries g) costs of the damages to the vehicle h) years of useful life and capitalization rate for the roads. Parameter f and g are further divided into heavy and light vehicles. It is concluded that if the characteristics of the cross section and of the barrier are defined, the total and capitalized social-economical cost will be the function of the only independent variable average daily traffic and the percentage of heavy vehicles. An application of the process is given.