Abstract: Reliability of the railway catenary system is a key to the safety of trains.In this paper, a mathematical model is established using the Markov theory and statistics based on the repairable characteristics of catenary.Availability, reliability and the mean failure time are derived.Reliability of the Bao-Cheng Railroad is analyzed and forecasted with the model.It is compared with the reliability of overseas catenary.Effective measures are proposed to improve catenary reliability.This study provides a theoretical basis and a new method for reliability design, maintenance and management of the railway system.

Key words: Markov theory, availability, catenary system, reliability analysis