The stress-endurance (S-N) method has been widely used in metal fatigue in the railway industry over many years. However, when this method is applied to rubber-like materials, it seems not as successful as when it is applied to metallic materials. Recently, an integrated fatigue evaluation programme has been carried out with the aim of improving the design of antivibration components in response to the increasing demands of the rail operating environment. This programme will also make simulations more reliable and relevant to industrial applications, especially for the fatigue design of rubber springs used in rail vehicle suspensions. The continuum mechanics (total life) approach has been used to characterize the fatigue life in terms of the cyclic stress range (S-N curve). It is suggested that the effective stress, s f , can be used as a parameter (taking three principal stress ranges into consideration) to evaluate fatigue failure. The initial verification of this approach has been carried out on two types of rubber spring. The results have shown good agreement between the fatigue test of the components and the simulation based on this approach.

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Rubber-to-metal bonded springs are vital antivibration components for rail vehicles. Metacone rubber springs are widely used as a primary spring on a rail vehicle ®tted at the wheel axle box. Nowadays the more demanding operating environment has made the design of such components more challenging than ever before. By using an integrated design±simulation±testing procedure it is possible to achieve the maximum fatigue capacity of the suspension components under a very tight space envelope. This note illustrates the procedure to achieve the high performance and the fatigue service life requirements for the suspension components.

An integrated real-time simulation and experimental programme has been carried out on an anti-vibration part used in the railway industry. This work, which was done at the authors' Technical Centre, was designed to ensure that any temperature rise inside an antivibration part does not exceed the design requirement in accelerated fatigue tests. Real-time simulation and testing have the advantages of giving the maximum temperature change when an anti-vibration component reaches a steady state and the time duration for each stage of the whole process. It is found from both testing and simulation that the energy loss per cycle of the rubber spring, under fixed dynamic amplitude, does not depend on the loading frequency. Therefore, the energy loss per cycle can be more easily obtained using a conventional quasi-static loading procedure, to reduce the cost and the time, than from conducting more complicated dynamic tests.Key rubber parameters obtained from the authors' material testing laboratory are presented here as important references for similar applications in railway industries. It is shown that this methodology is reliable and can be used to evaluate the temperature effects caused by dynamic loading.