Highly localized stresses generated at the gauge corner of the outer rail cause fatigue cracking. The longitudinal bending stresses in the rail underhead radius position are of special interest, as tension spikes have been identified at this location during in-track measurements under high axle load conditions. The tension spike is a result of vertical and lateral head bending on the web. This effect is highly localized and is additional to the stresses generated due to vertical and lateral bending of the whole rail profile (the so-called global bending). This study examined contact and bending stresses by modelling the rail on a discrete foundation using finite elements and by considering the loading to be a fully slipping elliptical Hertzian contact patch. The analysis revealed that the tensile longitudinal stress was highly dependent on several service conditions: the contact patch offset from the rail centreline, the ratio of lateral (L) to vertical (V) loads, the direction of lateral traction, foundation stiffness and seasonal temperature variations. The tension spike increases, and the depth below the contact surface at which the stresses become tensile reduces, as the contact patch offset and/or the L/V ratio increases. Both these enhance the tendency for rolling contact fatigue cracks to turn downwards and become transverse defects. This is because an increase in tensile bending stresses together with both residual and thermally induced stresses can facilitate cracks to turn perpendicular to the tensile stresses once they reach a critical length. Shear traction towards the gauge corner was found to be the most damaging phenomenon.


    Access

    Check access

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    Finite element modelling of the rail gauge corner and underhead radius stresses under heavy axle load conditions


    Contributors:
    Ranjha, S A (author) / Ding, K (author) / Mutton, P J (author) / Kapoor, A (author)


    Publication date :

    2012-05-01


    Size :

    13 pages




    Type of media :

    Article (Journal)


    Type of material :

    Electronic Resource


    Language :

    Unknown





    Fatigue Analysis of the Rail Underhead Radius under High Axle Load Conditions

    Ranjha, Sagheer Abbas / Mutton, Peter J. / Kapoor, Ajay | Tema Archive | 2014


    Rail defect growth under heavy axle load

    Garcia, Greg / Jeong, David Y. | IuD Bahn | 2003


    A continuous mainline rail turnout under heavy-axle-load

    Davi, David / Jimenez, Rafael | IuD Bahn | 2014


    Management of rail longitudinal forces under heavy axle load

    Read, David M. / Kish, Andrew / LoPresti, Joseph | IuD Bahn | 2005