Sökning: "rails"
Visar resultat 1 - 5 av 70 avhandlingar innehållade ordet rails.
1. Continuous Welded Railway Rails: Residual Stress Analyses, Fatigue Assessments and Experiments
Sammanfattning : Railway rails are today often continuously welded. This type of joint generally requires less maintenance than is needed for the bolted joints. It has also reduced wheel damage and made the ride more comfortable. However, these joints are subject to damage. LÄS MER
2. Rolling Contact Fatigue of Railway Rails with Emphasis on Crack Initiation
Sammanfattning : Increased traffic density and the heavier axle loads of modern trains have led to severe problems with rolling contact fatigue (RCF) which cause initiation of surface cracks in railheads. In this thesis, a specific type of surface crack, the head check, is studied numerically with emphasis on fatigue crack initiation. LÄS MER
3. Elastic-Plastic Fracture Mechanics and RCF in Rails
Sammanfattning : This thesis concerns issues regarding the modeling and numerical simulation of singularcracks and their propagation in the context of Rolling Contact Fatigue (RCF) in rails.Typically, such cracks are associated with squats and head-checks in the rail head. LÄS MER
4. Numerical simulation of crack growth and wear in rails
Sammanfattning : Wear and rolling contact fatigue (RCF) of rails are huge problems for the railway industry with increased world-wide occurrence during the last decades. It is, therefore, of high interest to develop tools for the prediction of wear and RCF which can be used to estimate rail life. LÄS MER
5. Numerical simulation of crack propagation and wear in rails
Sammanfattning : This thesis is concerned with rail deterioration due to Rolling Contact Fatigue (RCF) and wear. Focus lies primarily on numerical modelling and prediction, with the long-term objective of developing tools to be used for specifications and planning of rail maintenance. LÄS MER