Reliability Analysis Of Steel Rail

It's a major development trend to design structures with the reliability method in the field of structural design at home and abroad. To change the method of the railway track structures' design from deterministic method into reliability method not only is the development trend of the railway's technique, but also is the imperative demand of the present railway traffic. The steel rail is an important components of the railway track structures. The thesis has probed into the reliability of the steel rail which is located in the Continuous Welded Railway. The following are the thesis' major research contents and achievements.First, some fundamental theory and several regular calculation methods are introduced. And the paper centers on the introduction of the appliance of the Monte-Carlo method in the calculation of the steel rail' s reliability. The failure mode and the design reference period of the steel rail are discussed , and the steel rail's performance function at limit state is established too.Second, the random variables in reliability analysis of the steel rail are discussed. These random variables include the wheel load, the stiffness of the rubber pad and the bed, the temperature stress and the fatigue ultimate strength of the steel rail. And their probability distributions and parameters are discussed thoroughly.Last, the reliability of 50kg/m-rail and 60kg/m-rail is calculated by using the method combing the Mote-Carlo imitation with the finite element method. On the basis of the calibration method, the objective reliability index of the steel rail is recommended, and the problems of the present standards of the rail-wear limits are pointed out, and then the rail-wear limits are discussed. The paper putsforward that allowable vertical-wear limits of the 60kg/m-rail can be raised 5 mm,which has great economic value.