NUMERICAL ANALYSIS OF LOAD DISTRIBUTION IN RAILWAY TRACK UNDER WHEELSET

The results of numerical analysis of a load distribution in a railway track under wheelset are presented in the paper. Dynamic analysis was carried out using LS-DYNA computer code. Ballasted track with the rectilinear rail-line axis was taken into consideration. Finite element model of the track section was developed. The model included two rails, fastening systems, sleepers, ballast and the embankment. Fasteners and the ballast layer were modelled using 1-D massless discrete elements – springs and dampers. Sleepers were modelled as elastic beams. The embankment was reflected approximately by a rectangular prism with unmovable side and bottom boundary surfaces. Moving load was applied using simplified FE models of railway vehicles. Vertical forces were put in the wheel – rail contact points. Two types of the vehicles, and loads consequently, were considered – the first one including two single wheelsets whereas the second one was equipped with two classic 2-axle bogies. RAIL_TRACK and RAIL_TRAIN LS-DYNA’s modules were applied for simulating the vehicle – track interaction. Displacements of selected nodes as well as other characteristic values were registered during the numerical simulation. Contours of stress and displacements for selected moment of time were also presented as a result of the FE analysis. The study gave information about the behaviour of the railway track and foundation under load caused by single axle and 2-axle bogie. Obtained results were compared to those available in the literature and the technical instructions of railway design