Reliability Analysis of Wood Transmission Poles

The feasibility of probability-based design procedures for electrical transmission lines is discussed. Single pole structures have been selected in this initial study because of their simplicity as well as the lack of consistency in their design procedures. For the reliability analysis of a line, the paper emphasizes the design point, or advanced mean value second order method. All equations needed for a design point analysis are presented. These equations were implemented in the reliability program PAPOLE. The computer program can perform a reliability or design point analysis for a line consisting of poles with random properties and the line can be subjected to random wind and ice loads. Any probability distribution can be prescribed for the variables. Sample reliability analyses are presented. It is shown how reliability analyses of existing lines can be used to calibrate new proposed design procedures. A design procedure based on the (LRFD) Load Resistance Factor Design format is recommended.