ASSESSMENT OF DAMPING EFFICIENCY FOR RAIL VEHICLE SHOCK ABSORBERS BASED ON ACCELERATION MEASUREMENTS

Abstract

In this paper is developed a method for assessment of the damping efficiency of vertical shock absorbers used in secondary suspensions of railway vehicles. The method is based on the analysis of vertical accelerations recorded simultaneously in operating conditions on axle, bogie and car body. Using a Two Degree of Freedom (2DOF) linear system, it is shown that the average phase-difference between the band-pass filtered accelerations of bogy and car body depends only on the damping condition of secondary suspension dampers, being practically independent of that displayed by bogie dampers. An analytical relation is assessed between the values of this parameter and the values of equivalent damping ratio of secondary suspension. The method is illustrated using the experimental results obtained by vibration measurements conducted on a passenger railway car.