Sökning: "track settlement"

Visar resultat 1 - 5 av 10 avhandlingar innehållade orden track settlement.

  1. 1. Dynamic train/track interaction : hanging sleepers, track stiffness variations and track settlement

    Författare :Andreas Lundqvist; Linköpings universitet; []
    Nyckelord :TECHNOLOGY; TEKNIKVETENSKAP;

    Sammanfattning : Trains have been operating on ballasted tracks for over 150 years. During this time demands from the railway organisations and from the industry to increase axle loads and train speeds on the existing railway lines have increased. The reasons for this are both economial and environmental. LÄS MER

  2. 2. Wheel–Rail Impact Loads and Track Settlement in Railway Crossings

    Författare :Xin Li; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; vehicle--track dynamics; wheel--rail contact; track settlement; material modelling of ballast; Switches and crossings; turnout; cyclic loading; Green s functions;

    Sammanfattning : Turnouts (Switches & Crossings, S&C) are critical components of a railway track requiring regular maintenance and generating high life cycle costs. A main driver for the high maintenance costs is the need to repair and replace switch rails and crossings as these components are subjected to a severe load environment. LÄS MER

  3. 3. Simulation of track settlement in railway turnouts-An iterative approach

    Författare :Xin Li; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; track settlement; Railway switch and crossing; cyclic loading; visco-plasticity; vehicle‒track interaction; 3D finite element analysis; granular material; ballast;

    Sammanfattning : In this thesis, a methodology for simulation of track settlement in railway turnouts (switches andcrossings, S&C) is presented. The methodology predicts the accumulated settlement for a given setof traffic loads using an iterative and cross-disciplinary procedure. LÄS MER

  4. 4. Differential railway track settlement in a transition zone – Field measurements and numerical simulations

    Författare :Kourosh Nasrollahi; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fibre Bragg grating sensors; dynamic vehicle–track interaction; heavy haul traffic; non-linear track model; 3MB slab track; Transition zone; empirical settlement model; condition monitoring;

    Sammanfattning : In a transition zone between two different railway track forms, there is a discontinuity in track structure leading to a gradient in track stiffness. Examples include transitions between different superstructures, e.g., slab track to ballasted track, and/or between different substructures, e. LÄS MER

  5. 5. Cost-effective maintenance of railway track geometry : a shift from safety limits to maintenance limits

    Författare :Iman Arasteh Khouy; Peter Veit; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Drift och underhållsteknik; Operation and Maintenance Engineering;

    Sammanfattning : Railway infrastructure is a complex system which comprises different subsystems. Long life span is one of the important aspects of this prime mode of transport. However, the useful life of its assets is highly dependent on the maintenance and renewal strategy used during the assets’ life cycle. LÄS MER