A multi-scale tunnel product model providing coherent geometry and semantics

For the planning of large infrastructure projects, such as inner-city subways, widely differing scales have to be considered - ranging from the scale of several kilometers for the general routing of the subway down to centimeter scale for the detailed planning of subway stations and hubs. At the same time, the strongly inter-disciplinary character of these projects necessitates an intensive exchange of data between the individual stakeholders. Data exchange on a high semantic level is supported by the technology of product models. However, currently available product models do not support the multi-scale aspects required to properly handle large infrastructure models. This paper contributes to closing this technological gap by proposing a general methodology for developing multi-scale product models which combine semantic and geometrical aspects in a consistent and coherent manner. The methodology is illustrated by the development of a multi-scale product model for shield tunnels. In addition, methods for the automated preservation of the consistency of geometric representations at different scales are discussed.