Effect of Anti-Bending Bars on Vertical Vibrations of Passenger Carriage Body

High-speed passenger carriages with a long and light carriage body are sensitive to vertical vibration because the bending mode eigenfrequency falls within the most sensible frequency interval for the human being. Anti-bending bars (ABBs) are a passive means to raise the eigenfrequency of the bendin...

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Main Authors: Ioana-Izabela Apostol, Traian Mazilu, Mădălina Dumitriu
Format: Article
Language:English
Published: MDPI AG 2025-02-01
Series:Technologies
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Online Access:https://www.mdpi.com/2227-7080/13/2/73
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author Ioana-Izabela Apostol
Traian Mazilu
Mădălina Dumitriu
author_facet Ioana-Izabela Apostol
Traian Mazilu
Mădălina Dumitriu
author_sort Ioana-Izabela Apostol
collection DOAJ
description High-speed passenger carriages with a long and light carriage body are sensitive to vertical vibration because the bending mode eigenfrequency falls within the most sensible frequency interval for the human being. Anti-bending bars (ABBs) are a passive means to raise the eigenfrequency of the bending mode of the carriage body beyond the sensitive limit, ameliorating ride comfort. ABBs are two bars fixed via vertical supports under the carriage chassis on the longitudinal beams. ABBs resist the bending of the carriage body and can, therefore, increase the bending eigenfrequency beyond the sensitive limit, as necessary. In this paper, a new model for the ABBs, which takes into account the longitudinal stiffness of the ABBs, the three-direction stiffness of the fastening between the ABBs and the vertical supports and the vertical vibration modes of the ABBs via the Euler–Bernoulli beam theory and modal analysis, is incorporated in the 10 degrees of freedom model of a passenger carriage; this is to study the effect of the ABBs upon the running behaviour and ride comfort according to the specific regulations in the field. First, the frequency response functions (FRFs) of the passenger carriage with an ABB system are calculated and analysed, and then, the root mean square (r.m.s.) acceleration and the comfort index are evaluated in the carriage body centre in the context of a parametric study. The longitudinal stiffness of the fastening is critical to ensure the effectiveness of the ABB system. However, the effect of decreasing in the longitudinal stiffness of the fastening can be compensated by adopting longer ABBs.
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spelling doaj-art-65797d69a2de4f32aaf3b49f06e983502025-08-20T02:45:31ZengMDPI AGTechnologies2227-70802025-02-011327310.3390/technologies13020073Effect of Anti-Bending Bars on Vertical Vibrations of Passenger Carriage BodyIoana-Izabela Apostol0Traian Mazilu1Mădălina Dumitriu2Department of Railway Vehicles, National University of Science and Technology Politehnica Bucharest, 060042 Bucharest, RomaniaDepartment of Railway Vehicles, National University of Science and Technology Politehnica Bucharest, 060042 Bucharest, RomaniaDepartment of Railway Vehicles, National University of Science and Technology Politehnica Bucharest, 060042 Bucharest, RomaniaHigh-speed passenger carriages with a long and light carriage body are sensitive to vertical vibration because the bending mode eigenfrequency falls within the most sensible frequency interval for the human being. Anti-bending bars (ABBs) are a passive means to raise the eigenfrequency of the bending mode of the carriage body beyond the sensitive limit, ameliorating ride comfort. ABBs are two bars fixed via vertical supports under the carriage chassis on the longitudinal beams. ABBs resist the bending of the carriage body and can, therefore, increase the bending eigenfrequency beyond the sensitive limit, as necessary. In this paper, a new model for the ABBs, which takes into account the longitudinal stiffness of the ABBs, the three-direction stiffness of the fastening between the ABBs and the vertical supports and the vertical vibration modes of the ABBs via the Euler–Bernoulli beam theory and modal analysis, is incorporated in the 10 degrees of freedom model of a passenger carriage; this is to study the effect of the ABBs upon the running behaviour and ride comfort according to the specific regulations in the field. First, the frequency response functions (FRFs) of the passenger carriage with an ABB system are calculated and analysed, and then, the root mean square (r.m.s.) acceleration and the comfort index are evaluated in the carriage body centre in the context of a parametric study. The longitudinal stiffness of the fastening is critical to ensure the effectiveness of the ABB system. However, the effect of decreasing in the longitudinal stiffness of the fastening can be compensated by adopting longer ABBs.https://www.mdpi.com/2227-7080/13/2/73carriage bodyABBsEuler–Bernoulli beamfirst bending modefastening stiffnessrunning behaviour and comfort
spellingShingle Ioana-Izabela Apostol
Traian Mazilu
Mădălina Dumitriu
Effect of Anti-Bending Bars on Vertical Vibrations of Passenger Carriage Body
Technologies
carriage body
ABBs
Euler–Bernoulli beam
first bending mode
fastening stiffness
running behaviour and comfort
title Effect of Anti-Bending Bars on Vertical Vibrations of Passenger Carriage Body
title_full Effect of Anti-Bending Bars on Vertical Vibrations of Passenger Carriage Body
title_fullStr Effect of Anti-Bending Bars on Vertical Vibrations of Passenger Carriage Body
title_full_unstemmed Effect of Anti-Bending Bars on Vertical Vibrations of Passenger Carriage Body
title_short Effect of Anti-Bending Bars on Vertical Vibrations of Passenger Carriage Body
title_sort effect of anti bending bars on vertical vibrations of passenger carriage body
topic carriage body
ABBs
Euler–Bernoulli beam
first bending mode
fastening stiffness
running behaviour and comfort
url https://www.mdpi.com/2227-7080/13/2/73
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AT traianmazilu effectofantibendingbarsonverticalvibrationsofpassengercarriagebody
AT madalinadumitriu effectofantibendingbarsonverticalvibrationsofpassengercarriagebody