Capacity is partially a matter of quality versus quantity. Increasing capacity utilization
gives more scheduled waiting time in the timetable as well as more delays when trains are
operated. A common way to analyse capacity is to first make a timetable and then use it in
a simulation where trains are perturbed. This way it is possible to establish the scheduled
waiting time and the expected delays of the trains at the same time as market demands on
traffic, e.g. frequency of different train services, are considered. However, setting up
simulations are often time consuming and requires a lot of input data.
A method is developed with the objective to improve and speed up capacity analysis
of double track railway lines. It can be used for both timetable generation and timetable
simulation. The focus of this paper is to present the model and validate that it can simulate
timetables accurately. The model has a macroscopic representation of the railway
infrastructure and rolling stock while timetables and perturbations are modelled in more
detail. When resolving conflicts, the dispatching algorithm can consider several trains and
take into account how the dispatching decision affects the possibility to make good
decisions at the next station.
The validation is performed using the micro simulation tool RailSys as reference. The
validation covers a wide range of scenarios of different traffic density, timetable
heterogeneity, inter station distance and primary delays. The validation shows good
results and the conclusion is that despite the simplicity of the model, it is accurate enoug