Railway operations are sometimes perturbed by disruptions which impose a reorganization of the service plan. Such disruptions may be due to several causes, from external attacks to extreme weather conditions, but they all have the common characteristic of constraining the access to a part of the infrastructure. This requires the combined effort of infrastructure managers and railway undertakings for finding the most efficient alternative schedule to cope with the new constraints. In the Capacity4Rail FP7 European project, we study the disruption management process implemented in different European countries (UK, France, Spain and Sweden) and we define a formalization of the process capable of representing the current practice and its expected development. In particular, we formalize the common activities and, where possible, we advance generalizations, validating the result with the aid of the infrastructure managers. Through the analysis of this process, the needs of improvements in some specific activities can be pointed out, and different solutions can be envisioned. In this paper, we propose this formalization through the aid of SysML diagrams, with SysML being a standardised and open source modelling language for system engineering. The paper shows the applicability of the model in a large disruption handling process and provides some basic model properties validated using a model checking algorithm.