Abstract
This paper investigates three-dimensional (3D) rail vibrations under fastening constraint up to 5000 Hz and provides insights into rail vibration control by fastening parameters. A methodology is proposed, including experimental investigation and numerical simulations of rail vibrations. Three steps are considered: 1) experimental investigation of rail vibrations under fastening constraint; 2) validation and analysis of 3D finite element (FE) modeling of rail-fastening systems; 3) rail vibration control by fastening parameters. In Step 1, operating deflection shape (ODS) and synchronized multiple-acceleration wavelet (SMAW) measurements are applied to identify rail vibration modes and measure wave propagation characteristics under fastening constraint. In Step 2, a 3D FE model capable of reproducing the dynamic behaviors of rail-fastening up to 5000 Hz is developed to analyze rail vibrations and validated using measurements from Step 1. In Step 3, insights into the control of rail vibrations are gained by sensitivity analysis of fastening parameters using the validated 3D FE model from Step 2. The results indicate that (1) under fastening constraint, ODS measurement identifies vertical bending modes, longitudinal compression modes, and lateral bending modes of the rail with shifted frequencies and significantly reduced vibration amplitude compared to that of free rail. (2) Vertical wave attenuation of rail-fastening is relatively small between 1800 and 3600 Hz, and lateral wave attenuation presents a dominant peak at about 3800 Hz. (3) Compared to the vertical and lateral directions, the fastening system constrains the longitudinal rail vibrations less strongly. (4) The change of fastening stiffness and damping can control rail mode frequencies and their vibration amplitude, and influence the wave propagation velocities and attenuation along the rail.
Highlights
Rail vibrations play an essential role in wheel-rail dynamic interaction
Thomson et al [23] investigated the effect on the rolling noise of nonlinear railpad stiffness parameters, and the results indicated that stiffer railpads caused more considerable attenuation of rail vibration along the track and reduced the rail-radiated noise
We describe a systematic methodology for studying rail vibration modes and wave propagation under fastening constraint
Summary
Rail vibrations play an essential role in wheel-rail dynamic interaction. Problems in the field of railway systems, such as short pitch corrugation and rolling noise, are closely related to rail vibrations. Hempelmann and Knothe [1] and Grassie [2] reported that the rail vertical ‘pinned-pinned’ mode was the wavelength-fixing mechanism of short pitch corrugation. Li et al [3] concluded that the rail longitudinal vibration modes were dominant for short pitch corrugation initiation and consistency between the longitudinal and vertical modes determines its continuous growth. Rail vibrations can be seen as the superposition of a series of vibrational waves [4]. Thomson et al [4,5,6] linked the decay rate of the waves along the track
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
