A Theoretical Model of Rail Corrugation on a Slab Track

Abstract Recently, the emerging rail grinding method with open-structured abrasive belt based on pressing plate which adopts full contour copying grinding method to extend the working length of abrasive belt and is more suitable for preventative grinding and maintenance of rail corrugation in high-speed railway has been proposed. The essence of its grinding process is the complex nonlinear interaction among the pressing plate, abrasive belt and rail. The research on the contact mechanism of the rail grinding method with open-structured abrasive belt based on pressing plate is still very lacking, which limits the practical application of the emering rail grinding method to a certain extent. In this paper, a theoretical model of the contact between pressing plate, abrasive belt and rail is established. The contact area morphology and contact stress distribution were obtained, and validity of the theoretical model was verified by finite element simulation. At the same time, the distribution characteristics of contact stress under single concentrated force, uniform force and multiple concentrated force were studied based on the contact model. It is concluded that the multiple concentrated force is the optimal loading method, and the contact stress is more uniform, which is more conducive to repair the standard contour of rail.

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A Comparative Study on Vertical Dynamic Responses of Three Types of Elevated Railway Tracks Subjected to a Moving Train

Mathematical Problems in Engineering ◽

10.1155/2019/3290958 ◽

2019 ◽

Vol 2019 ◽

pp. 1-11 ◽

Cited By ~ 1

Author(s):

Li Shi ◽

Xiaoqiang Ye ◽

Pengfei Zhang ◽

Lin Guo

Keyword(s):

Theoretical Model ◽

Comparative Study ◽

Reaction Force ◽

Dynamic Responses ◽

Railway Track ◽

Steel Spring ◽

Slab Track ◽

Ballastless Track ◽

Different Types ◽

Moving Train

A theoretical model incorporating the moving train, the railway track, and the elevated viaduct is established and then solved using periodic theory in this paper. The vertical wheel/rail forces and the dynamic responses of track and viaduct girder are obtained and compared for three different types of tracks, i.e., the double-block ballastless track, the rubber-pad floating slab track, and the steel-spring floating slab track. It is observed that the rubber-pad and steel-spring floating slab tracks can reduce more than 10% of the wheel/rail force and the reaction force at girder supports, when compared to those of the double-block ballastless track. Especially, the steel-spring floating slab track develops an uplifting force larger than the installation force of the fastening clip, which may cause failure of the rail fastening system.

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Analysis on limiting value of rail corrugation of floating-slab track based on wheel/rail multi-point contact

Chinese Science Bulletin (Chinese Version) ◽

10.1360/n972018-01242 ◽

2019 ◽

Vol 64 (25) ◽

pp. 2590-2599

Author(s):

Yu Sun ◽

Jianjin Yang ◽

Shengyang Zhu ◽

Lianxin Zheng

Keyword(s):

Point Contact ◽

Rail Corrugation ◽

Slab Track ◽

Limiting Value

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SIMULATION OF WAVE PROPAGATION OF FLOATING SLAB TRACK-TUNNEL-SOIL SYSTEM BY 2D THEORETICAL MODEL

International Journal of Structural Stability and Dynamics ◽

10.1142/s021945541350051x ◽

2013 ◽

Vol 14 (01) ◽

pp. 1350051 ◽

Cited By ~ 8

Author(s):

BIAO ZHOU ◽

XIONG-YAO XIE ◽

Y. B. YANG

Keyword(s):

Theoretical Model ◽

Timoshenko Beam ◽

Soil Layer ◽

Coupled System ◽

Computationally Efficient ◽

Characteristic Analysis ◽

Soil System ◽

Soil Layers ◽

Slab Track ◽

Spring System

Presented herein is a computationally efficient 2D theoretical model for simulating the steady response of a floating slab track-tunnel-soil system. The track-tunnel coupled system is simplified as a beam-spring system and embedded in soil layers. The tunnel is modeled by a Timoshenko beam with its interaction with the soil layers accounted for by two transfer matrices, with each derived for the soil layer above and beneath the tunnel. The approach as proposed herein has been referred to as the Timoshenko beam-transfer matrix method (TTMM), that allows one to analyze the response of the coupled system, including the tunnel motion and soil stresses. The results obtained were compared with those furnished by the pipe-in-pipe (PIP) approach, and were found to be consistent for exciting frequencies smaller than the tunnel second-mode cut-on frequency. The origin of discrepancies was investigated by the dispersion characteristic analysis, which is attributed to the absence of several in-plane modes when the tunnel is simplified as a Timoshenko beam.

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A theoretical model for understanding dentists' behavior in treating patients with AIDS

Journal of Dental Education ◽

10.1002/j.0022-0337.1991.55.11.tb02589.x ◽

1991 ◽

Vol 55 (11) ◽

pp. 708-716 ◽

Cited By ~ 1

Author(s):

MS Chen

Keyword(s):

Theoretical Model

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A Model for Analyzing Suicide Prevention

Crisis ◽

10.1027//0227-5910.21.2.80 ◽

2000 ◽

Vol 21 (2) ◽

pp. 80-89 ◽

Cited By ~ 3

Author(s):

Maila Upanne

Keyword(s):

Risk Factors ◽

Theoretical Model ◽

Protective Factors ◽

Suicide Prevention ◽

Suicide Risk ◽

Practical Work ◽

Individual Risk ◽

Self Assessment ◽

Prevention Project ◽

Individual Risk Factors

This study monitored the evolution of psychologists' (n = 31) conceptions of suicide prevention over the 9-year course of the National Suicide Prevention Project in Finland and assessed the feasibility of the theoretical model for analyzing suicide prevention developed in earlier studies [ Upanne, 1999a , b ]. The study was formulated as a retrospective self-assessment where participants compared their earlier descriptions of suicide prevention with their current views. The changes in conceptions were analyzed and interpreted using both the model and the explanations given by the subjects themselves. The analysis proved the model to be a useful framework for revealing the essential features of prevention. The results showed that the freely-formulated ideas on prevention were more comprehensive than those evolved in practical work. Compared to the earlier findings, the conceptions among the group had shifted toward emphasizing a curative approach and the significance of individual risk factors. In particular, greater priority was focused on the acute suicide risk phase as a preventive target. Nonetheless, the overall structure of prevention ideology remained comprehensive and multifactorial, stressing multistage influencing. Promotive aims (protective factors) also remained part of the prevention paradigm. Practical working experiences enhanced the psychologists' sense of the difficulties of suicide prevention as well as their criticism and feeling of powerlessness.

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