Methodologies for designing railway plastic and composite sleepers

Sleeper is an important component of ballasted track. At present, sleeper is mainly made of wood, steel and concrete. In recent years, because of its good durability, corrosion resistance and easy transportation and laying, plastic and composite sleepers have gradually developed and applied in railway around the world. At present, the plastic and composite sleeper has not yet drawn up the corresponding design standards, only on the basis of engineering experience and related technical guidelines to design. This paper summarizes the service and design condition of different materials sleeper (wooden sleeper, steel sleeper, concrete sleeper and plastic and composite sleeper), compared the material characteristics of different kinds of sleeper, the main damages and the main factors affecting the damages. Through the analysis and comparison of allowable stress method and limit state method, the limit state design method is thought has more advantages. It is suggested to use the limit state method to carry out the relevant research work on the design of plastic and composite sleeper.