Measurement and analysis of mid wavelength rail irregularity

Groundborne vibrations are becoming more and more important as train speed increases. Longer wavelength rail and track defects are excited at such velocities and lead to potentially unacceptable annoyance also at long distances from the railway line. The paper critically compares European Standards currently in force on rail irregularity measurements and describes the results obtained extending the range of a trolley typically used only for short wavelengths assessment (related to noise). The practical possibility to measure comfortably wavelengths up to 3 m will be shown.