METHODOLOGY FOR EVALUATION OF SAFETY IMPROVEMENT ALTERNATIVES FOR UTILITY POLES

The object of this paper is to present the formulation and demonstration of a methodology for evaluation of safety improvement alternatives for utility poles. It is a total-annual-cost method of economic analysis, which features the calculation of expected annual accident and collision maintenance costs on the probabilities and severities of single-vehicle collisions with utility poles and other fixed objects on the roadside. The probabilities and severities of these collisions are in turn computed from a definition of the speed and volume of traffic, distribution of vehicle sizes, and the numbers, types, and locations of utility poles and other fixed objects on the roadside. The methodology can be used to evaluate several types of improvement alternatives, including multiple use of poles, relocation of poles, breakaway poles, impact-attenuation systems, and underground placement of utility lines. It can also be used to evaluate alternatives for a specific situation or for various combinations of traffic and roadside conditions in order to identify the circumstances for which each is most economical. The methodology is demonstrated for various traffic and roadside conditions on two hypothetical street sections typical of many arterial street sections in Lincoln, Nebraska. The results of this demonstration show the applicability of the methodology and serve to illustrate the sensitivity of the selection of the best the alternative to traffic and roadside conditions.