The reliability of many switches & crossings plays a vital role in guaranteeing traffic stability. Regular checks on their geometry, particularly specific dimensions, are traditionally done using geometric rulers or via measuring train, that take the above measurements in a ”dynamic” way. However, compared to traditional static techniques, this dynamic monitoring is sometimes too severe and leads to excessive interventions on the network. This research aims to bridge the gap between the new dynamic and the traditional geometric measurements. The objective is to understand and quantify, via experimental protocols and numerical modelling, the phenomenon of interaction between a vehicle and a switches & crossing, in a situation of dynamic movements (train) and deformations (track). Preliminary results from multibody simulations already make it possible to study different realistic scenarios and to measure forces, displacements at different levels (track, wheels). The model validation will be carried out via experimental campaigns with Infrabel, the Belgian railway infrastructure manager company, on a selected switches & crossing with their measuring train. Notably, these experimental campaigns provided valuable insights for the upcoming analysis and validation process.