In Rotterdam, the Netherlands, the new RandstadRail underground line is going to be built in the period 2004 - 2008. Approximately two-third of the 3.0 km long Statenweg route will be constructed using tunnel-boring techniques. The remaining part is built in deep conventional excavations (depth around 20 m), which are also used for line-up and dismantling of the tunnelling equipment. This paper highlights some of the geotechnical calculations as performed during the engineering of the excavations near the Rotterdam Centraal station railway yard. Special attention has been paid to the ground deformations of the railway yard embankment that are expected to occur during the excavation works, as very strict tolerances apply to railtrack position and elevation. Modelling of the excavation geometry for one- and two-dimensional geotechnical calculations revealed that quite a number of simplifications had to be made on following aspects: surface profile (embankment vs. street elevation), varying distance between excavation and embankment, supporting effect of perpendicular diaphragm walls, more or less independent behaviour of diaphragm wall sections, etc.. It has therefore been decided to perform additional three-dimensional computations. The selected software (Plaxis 3D) provided sufficient possibilities to account for all kinds of asymmetry within the geometry. Verification of the Plaxis 3D results was done through evaluation of the calculation results for a one-dimensional geometry by 1D-, 2D- and 3D calculation tools. The results from the 3D calculations show some typical features of soil behaviour, such as arching effects. The ground deformations on the railway embankment as derived from the output data have been used in the official procedures for obtaining permission for working close to, and partly on, terrain owned by railway company ProRail.