Dynamic Train/Track Interaction Including State–Dependent Track Properties and Flexible Vehicle Components

An existing state—space based numerical method (see Reference [1]) to simulate vertical dynamic interaction between a rolling train and a railway track has been improved and extended. The modified method allows for non—linear track model properties and flexible vehicle model components. Track model properties are separated into linear contributions corresponding to a non—loaded track configuration and increments which are state—dependent. Linear finite element models represent the train and the track modelled as separate components. Model reduction techniques are employed for computational efficiency. State—dependent track model properties tire accounted for by applying counter—acting state—dependent forces to the corresponding nodes of the linear track model. The train/track simulations are carried out in the time—domain. The need for a state—dependent track model is discussed with respect to laboratory and field measurements.