Measurement and analysis of the noise from and vibration in rapid transit elevated structures

An analytical model of the vibration transmitted to and noise radiated from an elevated structure during the passage of a train has been developed. Using the roughness and discontinuities on the wheel and rail running surfaces as the starting point, the model is capable of predicting the effect on noise radiation of a number of noise control treatments. Field measurements of noise and vibration on a New York City Transit Authority elevated structure before and after installation of resilient fasteners have been compared with model predictions using parameters derived from laboratory measurements with acceptable agreement. Results of both field measurements and analytical model studies indicate that on the most common types of elevated structures in rapid transit use that noise directly radiated by the wheel and rail is equally as important as noise radiated by the structure.