Capacity is an important factor for assessing a railway. Capacity limitations restrict the possibilities to adjust the service supply to the market demand and can lead to disturbances that affect the travellers negatively. For this reason, it is important that the available capacity and the effects of using it are estimated and assessed when benefits are analysed. However, estimations often focus on either socio-economic or capacity aspects only.
In this paper, a method for evaluating timetable alternatives using time equivalents by combining economic assessment and capacity analysis is developed. Parameters describing each alternative´s characteristics and their effect are stepwise added to an existing model. Both real and simulated delay statistics for express trains on a double-track line with dense, mixed traffic are used to first determine relevant input parameters and calibrate the model, and later compare different alternatives. The results show that the choice of input parameters for the delays and the way how to include them in the model affected the result to a large extent. That highlights the importance of making adequate classifications of data and choosing the right parameters. Simulation is suitable for estimating the effect of changes on reliability which is an important input in an estimation model combining capacity and socio-economic aspects.