Assessing the Damaging Effects of Railway Dynamic Wheel Loads on Railway Foundations

Dynamic train wheel loads, which can be significantly greater than static loads, occur because of a variety of factors and unless they are properly considered in track structural design, significant unplanned maintenance and premature track failure may result. This is particularly so for traditional ballasted railways built on soft foundations, because although ballast lends itself to maintenance, it is often problematic and costly to repair damaged foundations. A novel rigorous analytical–numerical approach is described to predict and characterize, for the first time, the damage to which railway foundations can be subjected as a result of dynamic loads. The approach marries a sophisticated three-dimensional dynamic model of the train–track system incorporating vertical track quality, foundation soil distress models, statistical analysis methods, and results of field investigation. The resulting analyses demonstrate that the magnitudes and distributions of dynamic loads are a function of train speed and t...