Font Size: 

The US Federal Rail and Transit Administrations (FRA/FTA) publish guidelines for railway noise and vibration purposes that show generic curves for estimating vibration from railway vehicles with distance. The data that were applied towards creating these generic vibration-propagation curves are not readily available to the general public. This paper compares the generic curves to theoretical estimates of vibration with distance based upon independent contributions from three components of groundborne vibration: surface waves, spherical/pressure waves, and shear waves. Utilizing various equations that are comprised by these three components, it has been found that it is not possible to recreate the generic curves that are promulgated by the US FRA/FTA organizations. A review of the differences between generic curves and theoretical ones suggests that the US FRA/FTA curves greatly overpredict groundborne vibration at distances beyond about 30 m. As such, this paper presents a theoretical equation comprised of surface, spherical, and shear waves that is thought to provide more accurate estimates of groundborne vibration from railways as a function of distance.