Sensitivity analysis on dynamic response of railway vehicle and ride index over curved bridges

Abstract

When a train passes over bridges, the magnitude of forces and accelerations is altered due to sudden changes in the track stiffness. These forces can change with the variation in operational parameters and are effective particularly in high-speed passenger trains, when studying ride index parameter. In addition, by increasing the speed, old bridge structures could fall into resonance, which has harmful consequences for both bridge and ride comfort index. Moreover, to harmonize the old bridges with the new operational conditions dynamic behavior of the vehicle and ride comfort need to be taken into account. In this paper, coupled vertical and roll vibration of a horizontally curved bridge are considered. During pass over the bridge, acceleration and ride comfort of a passenger vehicle are studied. The eccentric vertical and lateral forces are the major excitation sources in the analysis, an issue that is rarely noticed in the literature. A multi-body model of a normal wagon is built in three dimensions, passing over a horizontally curved bridge. The governing equations of the vehicle-bridge system are written, taking into account the wheel-rail interactions. The major variables are the cant, train speed, track quality, and radius of curvature. The paper studies the effects of the prescribed variables on ride comfort. The results show that track quality and cant have considerable influences on ride comfort index. The ride comfort is improved when the speed is approached to a so-called equivalent speed.

Effect of unsupported sleepers on dynamic behavior of running vehicles and ride comfort index

“…In order to consider the influence of various frequencies on the human body sensitivity, W z is multiplied by H f ð Þ vertical H f ð Þ lateral frequency filters. Finally, the comfort level is determined using W z approach in Zakeri et al 33 Table 3 shows ride comfort classification as proposed by Zakeri et al 33 Figure 9 illustrates the trends of rail displacement, wheel/rail contact force, driver cab acceleration, and ride comfort index with respect to locomotive speed and number of unsupported sleepers through the settlement region.…”

Vehicle Ride Comfort Analysis Based on Vehicle‐Bridge Coupled Vibration

“…It has become an important item in bridge engineering design to consider the influence of vehicle-bridge coupling vibration on vehicle ride comfort [12][13][14]. In recent years, the research on this subject has made some progress and obtained some achievements.…”

Use of measured accelerations from a passenger rail car to evaluate ride quality and track roughness – A case study

“…14 For passenger rail transit, ride quality and comfort are established indices used to assess the combined performance of the vehicle and track International standards ISO 2631-1: 1997 15 ; CEN, ENV 12299: 1999 16 ; UIC 513, 1995 17 ; JIS E4023, 1990, 18 as well as Sperling and Betzhold 19 give indications of passengers' reactions to vibrations reported in public transport. This has been utilized, particularly in high-speed rail operations in Japan, 20 Europe, 21 and South Korea, 22 with a greater focus on vehicle dynamics, analysis of bridges, 23,24 soft subgrades, 25 track features using crowdsourced smartphone data, 26,27 or considering track geometry parameters and rolling stock dynamic properties. 28,29 Surface roughness and alignment roughness are important geometry parameters for assessing the quality of track geometry and safe operation of rail transit.…”